// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/renderer_host/navigator.h"

#include <tuple>
#include <utility>

#include "base/check_op.h"
#include "base/debug/dump_without_crashing.h"
#include "base/metrics/histogram_functions.h"
#include "base/notreached.h"
#include "base/strings/strcat.h"
#include "base/strings/string_util.h"
#include "base/time/time.h"
#include "base/types/optional_util.h"
#include "content/browser/process_lock.h"
#include "content/browser/renderer_host/debug_urls.h"
#include "content/browser/renderer_host/frame_tree.h"
#include "content/browser/renderer_host/frame_tree_node.h"
#include "content/browser/renderer_host/initiator_navigation_state_impl.h"
#include "content/browser/renderer_host/navigation_controller_impl.h"
#include "content/browser/renderer_host/navigation_entry_impl.h"
#include "content/browser/renderer_host/navigation_request.h"
#include "content/browser/renderer_host/navigation_request_info.h"
#include "content/browser/renderer_host/navigation_transitions/navigation_transition_utils.h"
#include "content/browser/renderer_host/navigator_delegate.h"
#include "content/browser/renderer_host/render_frame_host_delegate.h"
#include "content/browser/renderer_host/render_frame_host_impl.h"
#include "content/browser/renderer_host/render_view_host_impl.h"
#include "content/browser/security/cpsp/child_process_security_policy_impl.h"
#include "content/browser/site_info.h"
#include "content/browser/site_instance_impl.h"
#include "content/browser/web_package/prefetched_signed_exchange_cache.h"
#include "content/browser/webui/web_ui_controller_factory_registry.h"
#include "content/browser/webui/web_ui_impl.h"
#include "content/common/content_navigation_policy.h"
#include "content/common/features.h"
#include "content/common/navigation_params_utils.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/disallow_activation_reason.h"
#include "content/public/browser/global_request_id.h"
#include "content/public/browser/invalidate_type.h"
#include "content/public/browser/navigation_controller.h"
#include "content/public/browser/navigation_details.h"
#include "content/public/browser/page_navigator.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/restore_type.h"
#include "content/public/browser/web_ui_controller.h"
#include "content/public/common/bindings_policy.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_constants.h"
#include "content/public/common/url_utils.h"
#include "net/base/net_errors.h"
#include "net/base/schemeful_site.h"
#include "services/metrics/public/cpp/ukm_builders.h"
#include "services/metrics/public/cpp/ukm_recorder.h"
#include "services/metrics/public/cpp/ukm_source_id.h"
#include "services/network/public/mojom/url_loader_factory.mojom.h"
#include "third_party/blink/public/common/loader/inter_process_time_ticks_converter.h"
#include "third_party/blink/public/common/navigation/navigation_policy.h"
#include "third_party/blink/public/mojom/navigation/navigation_params.mojom.h"
#include "url/gurl.h"
#include "url/url_util.h"

namespace content {

namespace {

using WebFeature = blink::mojom::WebFeature;
using CrossOriginOpenerPolicyValue =
    network::mojom::CrossOriginOpenerPolicyValue;
using CrossOriginEmbedderPolicyValue =
    network::mojom::CrossOriginEmbedderPolicyValue;
using DocumentIsolationPolicyValue =
    network::mojom::DocumentIsolationPolicyValue;

// Map Cross-Origin-Opener-Policy header value to its corresponding WebFeature.
std::optional<WebFeature> FeatureCoop(CrossOriginOpenerPolicyValue value) {
  switch (value) {
    case CrossOriginOpenerPolicyValue::kUnsafeNone:
      return std::nullopt;
    case CrossOriginOpenerPolicyValue::kSameOrigin:
      return WebFeature::kCrossOriginOpenerPolicySameOrigin;
    case CrossOriginOpenerPolicyValue::kSameOriginAllowPopups:
      return WebFeature::kCrossOriginOpenerPolicySameOriginAllowPopups;
    case CrossOriginOpenerPolicyValue::kNoopenerAllowPopups:
      return WebFeature::kCrossOriginOpenerPolicyNoopenerAllowPopups;
    case CrossOriginOpenerPolicyValue::kSameOriginPlusCoep:
      return WebFeature::kCoopAndCoepIsolated;
  }
}

// Map Cross-Origin-Opener-Policy-Report-Only header value to its corresponding
// WebFeature.
std::optional<WebFeature> FeatureCoopRO(CrossOriginOpenerPolicyValue value) {
  switch (value) {
    case CrossOriginOpenerPolicyValue::kUnsafeNone:
      return std::nullopt;
    case CrossOriginOpenerPolicyValue::kSameOrigin:
      return WebFeature::kCrossOriginOpenerPolicySameOriginReportOnly;
    case CrossOriginOpenerPolicyValue::kSameOriginAllowPopups:
      return WebFeature::
          kCrossOriginOpenerPolicySameOriginAllowPopupsReportOnly;
    case CrossOriginOpenerPolicyValue::kNoopenerAllowPopups:
      return WebFeature::kCrossOriginOpenerPolicyNoopenerAllowPopupsReportOnly;
    case CrossOriginOpenerPolicyValue::kSameOriginPlusCoep:
      return WebFeature::kCoopAndCoepIsolatedReportOnly;
  }
}

// Map Cross-Origin-Embedder-Policy header value to its
// corresponding WebFeature.
std::optional<WebFeature> FeatureCoep(CrossOriginEmbedderPolicyValue value) {
  switch (value) {
    case CrossOriginEmbedderPolicyValue::kNone:
      return std::nullopt;
    case CrossOriginEmbedderPolicyValue::kCredentialless:
      return WebFeature::kCrossOriginEmbedderPolicyCredentialless;
    case CrossOriginEmbedderPolicyValue::kRequireCorp:
      return WebFeature::kCrossOriginEmbedderPolicyRequireCorp;
  }
}

// Map Cross-Origin-Embedder-Policy-Report-Only header value to its
// corresponding WebFeature.
std::optional<WebFeature> FeatureCoepRO(CrossOriginEmbedderPolicyValue value) {
  switch (value) {
    case CrossOriginEmbedderPolicyValue::kNone:
      return std::nullopt;
    case CrossOriginEmbedderPolicyValue::kCredentialless:
      return WebFeature::kCrossOriginEmbedderPolicyCredentiallessReportOnly;
    case CrossOriginEmbedderPolicyValue::kRequireCorp:
      return WebFeature::kCrossOriginEmbedderPolicyRequireCorpReportOnly;
  }
}

// Map Document-Isolation-Policy header value to its corresponding WebFeature.
std::optional<WebFeature> FeatureDip(DocumentIsolationPolicyValue value) {
  switch (value) {
    case DocumentIsolationPolicyValue::kNone:
      return std::nullopt;
    case DocumentIsolationPolicyValue::kIsolateAndRequireCorp:
      return WebFeature::kDocumentIsolationPolicyRequireCorp;
    case DocumentIsolationPolicyValue::kIsolateAndCredentialless:
      return WebFeature::kDocumentIsolationPolicyCredentialless;
  }
}

ukm::SourceId GetPageUkmSourceId(RenderFrameHost& rfh) {
  // RenderFrameHost::GetPageUkmSourceId does not support being called in the
  // prerendering state, because our data collection policy disallows collecting
  // UKMs while prerendering. This function changes calls within Navigator to
  // use kInvalidSourceId in this state, since most other callers outside
  // Navigator can avoid the call during prerendering.
  // If a future use case needs a UKM during prerendering, please see
  // //content/browser/preloading/prerender/README.md and consult the Prerender
  // team.
  if (rfh.IsInLifecycleState(RenderFrameHost::LifecycleState::kPrerendering)) {
    return ukm::kInvalidSourceId;
  }
  return rfh.GetPageUkmSourceId();
}

// TODO(titouan): Move the feature computation logic into `NavigationRequest`,
// and use `NavigationRequest::TakeWebFeatureToLog()` to record them later.
void RecordWebPlatformSecurityMetrics(RenderFrameHostImpl* rfh,
                                      bool has_embedding_control,
                                      bool is_error_page) {
  ContentBrowserClient* client = GetContentClient()->browser();

  auto log = [&](std::optional<WebFeature> feature) {
    if (feature)
      client->LogWebFeatureForCurrentPage(rfh, feature.value());
  };

  // [COOP]
  if (rfh->IsInPrimaryMainFrame()) {
    log(FeatureCoop(rfh->cross_origin_opener_policy().value));
    log(FeatureCoopRO(rfh->cross_origin_opener_policy().report_only_value));

    if (rfh->cross_origin_opener_policy().reporting_endpoint ||
        rfh->cross_origin_opener_policy().report_only_reporting_endpoint) {
      log(WebFeature::kCrossOriginOpenerPolicyReporting);
    }
  }

  // [COEP]
  log(FeatureCoep(rfh->cross_origin_embedder_policy().value));
  log(FeatureCoepRO(rfh->cross_origin_embedder_policy().report_only_value));

  // Document-Isolation-Policy
  log(FeatureDip(rfh->policy_container_host()
                     ->policies()
                     .document_isolation_policy.value));

  // Record iframes embedded in cross-origin contexts without a CSP
  // frame-ancestor directive.
  bool is_embedded_in_cross_origin_context = false;
  RenderFrameHostImpl* parent = rfh->GetParent();
  while (parent) {
    if (!parent->GetLastCommittedOrigin().IsSameOriginWith(
            rfh->GetLastCommittedOrigin())) {
      is_embedded_in_cross_origin_context = true;
      break;
    }
    parent = parent->GetParent();
  }

  if (is_embedded_in_cross_origin_context && !has_embedding_control &&
      !is_error_page) {
    log(WebFeature::kCrossOriginSubframeWithoutEmbeddingControl);
    RenderFrameHostImpl* main_frame = rfh->GetMainFrame();
    ukm::builders::CrossOriginSubframeWithoutEmbeddingControl(
        GetPageUkmSourceId(*main_frame))
        .SetSubframeEmbedded(1)
        .Record(ukm::UkmRecorder::Get());
  }

  // Record whether <iframe> with the credentialless attribute contains
  // sandboxed document or not. Please note:
  // - This is recorded once for every new document in the iframe.
  // - It excludes nested document that are credentialless only by inheritance.
  // - It would have been better to take a snapshot of the frame.credentialless
  //   attribute at the beginning of the navigation, as opposed to when the
  //   new document has been created, because it might have changed. Still, it
  //   is good enough, a priori.
  if (rfh->frame_tree_node()->Credentialless()) {
    base::UmaHistogramBoolean(
        "Navigation.AnonymousIframeIsSandboxed",
        rfh->active_sandbox_flags() != network::mojom::WebSandboxFlags::kNone);
  }

  // Check if the navigation resulted in having same-origin documents in pages
  // with different COOP status inside the browsing context group.
  RenderFrameHostImpl* top_level_document =
      rfh->frame_tree_node()->frame_tree().GetMainFrame();
  network::mojom::CrossOriginOpenerPolicyValue page_coop =
      top_level_document->cross_origin_opener_policy().value;
  for (RenderFrameHostImpl* other_tld :
       rfh->delegate()->GetActiveTopLevelDocumentsInBrowsingContextGroup(rfh)) {
    network::mojom::CrossOriginOpenerPolicyValue other_page_coop =
        other_tld->cross_origin_opener_policy().value;
    if (page_coop == other_page_coop)
      continue;

    using CoopValue = network::mojom::CrossOriginOpenerPolicyValue;
    DCHECK((page_coop == CoopValue::kSameOriginAllowPopups &&
            other_page_coop == CoopValue::kUnsafeNone) ||
           (page_coop == CoopValue::kUnsafeNone &&
            other_page_coop == CoopValue::kSameOriginAllowPopups) ||
           (page_coop == CoopValue::kUnsafeNone &&
            other_page_coop == CoopValue::kNoopenerAllowPopups) ||
           (page_coop == CoopValue::kSameOriginAllowPopups &&
            other_page_coop == CoopValue::kNoopenerAllowPopups));
    for (FrameTreeNode* frame_tree_node :
         other_tld->frame_tree_node()->frame_tree().Nodes()) {
      RenderFrameHostImpl* other_rfh = frame_tree_node->current_frame_host();
      if (other_rfh->lifecycle_state() ==
              RenderFrameHostImpl::LifecycleStateImpl::kActive &&
          rfh->GetLastCommittedOrigin().IsSameOriginWith(
              other_rfh->GetLastCommittedOrigin())) {
        // Always log the feature on the COOP same-origin-allow-popups page,
        // since this is the spec we are trying to change.
        RenderFrameHostImpl* rfh_to_log =
            page_coop == CoopValue::kSameOriginAllowPopups ? rfh : other_rfh;
        client->LogWebFeatureForCurrentPage(
            rfh_to_log, blink::mojom::WebFeature::
                            kSameOriginDocumentsWithDifferentCOOPStatus);
      }
    }
  }
}

// Records the fact that `rfh` made use of `web_features`.
void RecordMetrics(RenderFrameHostImpl& rfh,
                   const std::vector<blink::mojom::WebFeature>& web_features) {
  ContentBrowserClient& client = *GetContentClient()->browser();
  for (const auto feature : web_features) {
    client.LogWebFeatureForCurrentPage(&rfh, feature);
  }
}

bool HasEmbeddingControl(NavigationRequest* navigation_request) {
  if (!navigation_request->response())
    // This navigation did not result in a network request. The embedding of
    // the frame is not controlled by network headers.
    return true;

  // Check if the request has a CSP frame-ancestor directive.
  for (const auto& csp : navigation_request->response()
                             ->parsed_headers->content_security_policy) {
    if (csp->header->type ==
            network::mojom::ContentSecurityPolicyType::kEnforce &&
        csp->directives.contains(
            network::mojom::CSPDirectiveName::FrameAncestors)) {
      return true;
    }
  }

  return false;
}

}  // namespace

struct Navigator::NavigationMetricsData {
  NavigationMetricsData(base::TimeTicks start_time,
                        GURL url,
                        ukm::SourceId ukm_source_id,
                        bool is_browser_initiated_before_unload)
      : start_time_(start_time),
        url_(url),
        ukm_source_id_(ukm_source_id),
        is_browser_initiated_before_unload_(
            is_browser_initiated_before_unload) {}

  base::TimeTicks start_time_;
  GURL url_;
  ukm::SourceId ukm_source_id_;
  bool is_browser_initiated_before_unload_;

  // Timestamps before_unload_(start|end)_ give the time it took to run
  // beforeunloads dispatched from the browser process. For browser-initiated
  // navigations this includes all frames (all beforeunload handlers on a page).
  // For renderer-initiated navigations this just includes OOPIFs since local
  // beforeunloads will have been run in the renderer before dispatching the
  // navigation IPC.
  std::optional<base::TimeTicks> before_unload_start_;
  std::optional<base::TimeTicks> before_unload_end_;

  // Time at which the browser process received a navigation request and
  // dispatched beforeunloads to the renderer.
  std::optional<base::TimeTicks> before_unload_sent_;

  // Timestamps renderer_before_unload_(start|end)_ give the time it took to run
  // beforeunloads for local frames in a renderer-initiated navigation, prior to
  // notifying the browser process about the navigation.
  std::optional<base::TimeTicks> renderer_before_unload_start_;
  std::optional<base::TimeTicks> renderer_before_unload_end_;

  // Time at which the browser process dispatched the CommitNavigation to the
  // renderer.
  std::optional<base::TimeTicks> commit_navigation_sent_;
};

Navigator::Navigator(
    BrowserContext* browser_context,
    FrameTree& frame_tree,
    NavigatorDelegate* delegate,
    NavigationControllerDelegate* navigation_controller_delegate)
    : controller_(browser_context, frame_tree, navigation_controller_delegate),
      delegate_(delegate) {}

Navigator::~Navigator() = default;

// static
bool Navigator::CheckWebUIRendererDoesNotDisplayNormalURL(
    RenderFrameHostImpl* render_frame_host,
    const UrlInfo& url_info,
    bool is_renderer_initiated_check) {
  const GURL& url = url_info.url;
  // In single process mode, everything runs in the same process, so the checks
  // below are irrelevant.
  if (RenderProcessHost::run_renderer_in_process())
    return true;

  // In the case of error page process, any URL is allowed to commit.
  ProcessLock process_lock = render_frame_host->GetProcess()->GetProcessLock();
  if (process_lock.is_error_page())
    return true;

  bool frame_has_webui_bindings =
      render_frame_host->GetEnabledBindings().HasAny(kWebUIBindingsPolicySet);
  bool is_allowed_in_web_ui_renderer =
      WebUIControllerFactoryRegistry::GetInstance()->IsURLAcceptableForWebUI(
          render_frame_host->GetProcess()->GetBrowserContext(), url);

  // Embedders might disable locking for WebUI URLs, which is bad idea, however
  // this method should take this into account.
  SiteInstanceImpl* site_instance = render_frame_host->GetSiteInstance();
  SiteInfo site_info = site_instance->DeriveSiteInfo(url_info);
  bool should_lock_process =
      site_info.ShouldLockProcessToSite(site_instance->GetIsolationContext());

  // If the |render_frame_host| has any WebUI bindings, disallow URLs that are
  // not allowed in a WebUI renderer process.
  if (frame_has_webui_bindings) {
    // The process itself must have WebUI bit in the security policy.
    // Otherwise it indicates that there is a bug in browser process logic and
    // the browser process must be terminated.
    // TODO(nasko): Convert to CHECK() once it is confirmed this is not
    // violated in reality.
    if (!ChildProcessSecurityPolicyImpl::GetInstance()->HasWebUIBindings(
            render_frame_host->GetProcess()->GetDeprecatedID())) {
      base::debug::DumpWithoutCrashing();
    }

    // Check whether the process must be locked and if so that the process lock
    // is indeed in place.
    if (should_lock_process && !process_lock.IsLockedToSite()) {
      return false;
    }

    // There must be a WebUI on the frame.
    if (!render_frame_host->web_ui())
      return false;

    // The |url| must be allowed in a WebUI process if the frame has WebUI.
    if (!is_allowed_in_web_ui_renderer) {
      // If this method is called in response to IPC message from the renderer
      // process, it should be terminated, otherwise it is a bug in the
      // navigation logic and the browser process should be terminated to avoid
      // exposing users to security issues.
      CHECK(is_renderer_initiated_check);
      return false;
    }
  }

  // If `url` is one that is allowed in WebUI renderer process, ensure that its
  // origin is either opaque or its process lock matches the RFH process lock.
  // As an example, the origin may be opaque if a WebUI navigation resulted in
  // an error page.
  //
  // TODO(alexmos): Currently, `is_allowed_in_web_ui_renderer` is unexpectedly
  // true for about:blank and renderer debug URLs, even when they commit with
  // an origin that is not allowed into a WebUI renderer.  For now, these cases
  // are also skipped via the origin opaqueness check, but
  // `is_allowed_in_web_ui_renderer` should be strengthened to not be true in
  // this case so that the checks above also apply.  See
  // https://crbug.com/1320402.
  if (is_allowed_in_web_ui_renderer) {
    // Verify `site_info`'s process lock matches the RFH's process lock, if one
    // is in place.
    if (should_lock_process) {
      if (!url::Origin::Create(url).opaque() &&
          process_lock != ProcessLock::FromSiteInfo(site_info)) {
        return false;
      }
    }
  }

  return true;
}

// A renderer-initiated navigation should be ignored iff a) there is an ongoing
// request b) which is browser initiated or a history traversal and c) the
// renderer request is not user-initiated.
// Renderer-initiated history traversals cause navigations to be ignored for
// compatibility reasons - this behavior is asserted by several web platform
// tests.
// static
bool Navigator::ShouldIgnoreIncomingRendererRequest(
    const NavigationRequest* ongoing_navigation_request,
    bool has_user_gesture) {
  return ongoing_navigation_request &&
         (ongoing_navigation_request->browser_initiated() ||
          NavigationTypeUtils::IsHistory(
              ongoing_navigation_request->common_params().navigation_type)) &&
         !has_user_gesture;
}

NavigatorDelegate* Navigator::GetDelegate() {
  return delegate_;
}

bool Navigator::StartHistoryNavigationInNewSubframe(
    RenderFrameHostImpl* render_frame_host,
    mojo::PendingAssociatedRemote<mojom::NavigationClient>* navigation_client,
    blink::LocalFrameToken initiator_frame_token,
    ChildProcessId initiator_process_id,
    scoped_refptr<InitiatorNavigationState> initiator_navigation_state,
    base::TimeTicks actual_navigation_start) {
  return controller_.StartHistoryNavigationInNewSubframe(
      render_frame_host, navigation_client, initiator_frame_token,
      initiator_process_id, initiator_navigation_state,
      actual_navigation_start);
}

void Navigator::DidNavigate(
    RenderFrameHostImpl* render_frame_host,
    const mojom::DidCommitProvisionalLoadParams& params,
    std::unique_ptr<NavigationRequest> navigation_request,
    bool was_within_same_document,
    bool caused_by_ad) {
  DCHECK(navigation_request);
  FrameTreeNode* frame_tree_node = render_frame_host->frame_tree_node();
  FrameTree& frame_tree = frame_tree_node->frame_tree();
  DCHECK_EQ(&frame_tree, &controller_.frame_tree());

  base::WeakPtr<RenderFrameHostImpl> old_frame_host =
      frame_tree_node->render_manager()->current_frame_host()->GetWeakPtr();

  // Save the activation status of the previous page here before it gets reset
  // in FrameTreeNode::UpdateUserActivationState. Look at the root since the
  // activation status for all frames on the page is aggregated in the main
  // frame of the current frame tree (but not across nested frame trees).
  bool previous_document_history_intervention_activation =
      old_frame_host->GetMainFrame()
          ->HasStickyUserActivationForHistoryIntervention();

  if (auto& old_page_info = navigation_request->commit_params().old_page_info) {
    // This is a same-site main-frame navigation where we did a proactive
    // BrowsingInstance swap but we're reusing the old page's process, and we
    // have dispatched the pagehide and visibilitychange handlers of the old
    // page when we committed the new page.
    auto* page_lifecycle_state_manager =
        old_frame_host->render_view_host()->GetPageLifecycleStateManager();
    page_lifecycle_state_manager->DidSetPagehideDispatchDuringNewPageCommit(
        std::move(old_page_info->new_lifecycle_state_for_old_page));
  }

  // If a frame claims the navigation was same-document, it must be the current
  // frame, not a pending one.
  if (was_within_same_document && render_frame_host != old_frame_host.get()) {
    was_within_same_document = false;
  }

#if BUILDFLAG(IS_ANDROID)
  // This is the last point where the browser still embeds the `viz::Surface` of
  // the old page. The next `WebContentsImpl::DidNavigateMainFramePreCommit()`
  // will hide the old View, and the
  // `RenderFrameHostManager::DidNavigateFrame()` will subsequently unload the
  // old page and show the new View.
  if (!was_within_same_document) {
    NavigationTransitionUtils::
        CaptureNavigationEntryScreenshotForCrossDocumentNavigations(
            *navigation_request, /*did_receive_commit_ack=*/true);
  }
#endif  // BUILDFLAG(IS_ANDROID)

  // Run tasks that must execute just before the commit.
  base::WeakPtr<RenderFrameHostImpl> weak_rfh = render_frame_host->GetWeakPtr();
  delegate_->DidNavigateAnyFramePreCommit(navigation_request.get(),
                                          was_within_same_document);

  // NOTE: the pre commit tasks may result in the destruction of the render
  // frame host, in which case we should exit this method early.
  if (!weak_rfh) {
    return;
  }

  if (ui::PageTransitionIsMainFrame(params.transition)) {
    delegate_->DidNavigateMainFramePreCommit(navigation_request.get(),
                                             was_within_same_document);
  }

  // The current RenderFrameHost might change after the call below if a
  // RenderFrameHost swap happens, so save the current RenderFrameHost's id in
  // the NavigationRequest.
  navigation_request->set_previous_render_frame_host_id(
      old_frame_host->GetGlobalId());

  // Store this information before DidNavigateFrame() potentially swaps RFHs.
  url::Origin old_frame_origin = old_frame_host->GetLastCommittedOrigin();

  // RenderFrameHostImpl::DidNavigate will update the url, and may cause the
  // node to consider itself no longer on the initial empty document. Record
  // whether we're leaving the initial empty document before that.
  bool was_on_initial_empty_document =
      frame_tree_node->is_on_initial_empty_document();

  // Allow main frame paint holding in the following cases:
  //  - We don't have an animated transition. See crbug.com/360844863.
  //  - At least one of the following conditions is true:
  //    - This is a navigation from the initial document (in cases where this is
  //      a brand new tab that didn't inherit another origin from an opener).
  //      This part helps with tests. See crbug.com/367623929.
  //    - This is a same origin navigation (or we're not limiting cross-origin
  //      paint holding)
  //    - There is a user activation. This means that the user interacted with
  //      the page. Commonly used attacks are done without user activation --
  //      which will not enable paint holding. However, if the user interacts
  //      with the page, we treat it as a valid case for paint holding.
  //    - The client allows non-activated cross origin paintholding, which is
  //      currently the case with webview.
  //
  // See https://issues.chromium.org/40942531 for reasons we limit paint
  // holding.
  ContentBrowserClient* client = GetContentClient()->browser();
  const bool allow_paint_holding_for_initial_empty_document =
      was_on_initial_empty_document && old_frame_origin.opaque() &&
      !old_frame_origin.GetTupleOrPrecursorTupleIfOpaque().IsValid();
  const bool allow_main_frame_paint_holding =
      !navigation_request->was_initiated_by_animated_transition() &&
      (allow_paint_holding_for_initial_empty_document ||
       old_frame_origin.IsSameOriginWith(params.origin) ||
       old_frame_host->HasStickyUserActivation() ||
       client->AllowNonActivatedCrossOriginPaintHolding() ||
       !base::FeatureList::IsEnabled(
           features::kLimitCrossOriginNonActivatedPaintHolding));

  // Only allow subframe paint holding for same origin.
  const bool allow_subframe_paint_holding =
      old_frame_origin.IsSameOriginWith(params.origin);

  // DidNavigateFrame() must be called before replicating the new origin and
  // other properties to proxies.  This is because it destroys the subframes of
  // the frame we're navigating from, which might trigger those subframes to
  // run unload handlers.  Those unload handlers should still see the old
  // frame's origin.  See https://crbug.com/825283.
  const bool allow_paint_holding = frame_tree_node->IsMainFrame()
                                       ? allow_main_frame_paint_holding
                                       : allow_subframe_paint_holding;
  const RenderFrameHostManager::ViewTransitionCommitInfo
      view_transition_commit_info(
          navigation_request->GetViewTransitionResources(),
          navigation_request->HasViewTransitionDelayLayerTreeViewDeletion());
  const bool is_backward_navigation =
      navigation_request->GetNavigationEntryOffset() < 0;
  frame_tree_node->render_manager()->DidNavigateFrame(
      render_frame_host,
      navigation_request->common_params().has_possibly_filtered_user_gesture,
      was_within_same_document,
      navigation_request->browsing_context_group_swap()
          .ShouldClearProxiesOnCommit(),
      navigation_request->commit_params().frame_policy, allow_paint_holding,
      view_transition_commit_info, is_backward_navigation);

  // The main frame, same site, and cross-site navigation checks for user
  // activation mirror the checks in DocumentLoader::CommitNavigation() (note:
  // CommitNavigation() is not called for same-document navigations, which is
  // why we have the !was_within_same_document check). This is done to prevent
  // newly navigated pages from re-using the sticky user activation state from
  // the previously navigated page in the frame. We persist user activation
  // across same-site navigations for compatibility reasons with user
  // activation, and does not need to match the same-site checks used in the
  // process model. See: crbug.com/736415, and crbug.com/40228985 for the
  // specific regression that resulted in this requirement.
  //
  // Since we're only clearing or providing a new activation, we don't care if
  // `UpdateUserActivationState` succeeds or not.
  if (!was_within_same_document) {
    if (!navigation_request->commit_params()
             .should_have_sticky_user_activation) {
      std::ignore = frame_tree_node->UpdateUserActivationState(
          blink::mojom::UserActivationUpdateType::kClearActivation,
          blink::mojom::UserActivationNotificationType::kNone);
    } else {
      std::ignore = frame_tree_node->UpdateUserActivationState(
          blink::mojom::UserActivationUpdateType::kNotifyActivationStickyOnly,
          blink::mojom::UserActivationNotificationType::kNone);
    }
  }

  // Save the new page's origin and other properties, and replicate them to
  // proxies, including the proxy created in DidNavigateFrame() to replace the
  // old frame in cross-process navigation cases. Note that the origin-related
  // bits are set separately, through `SetLastCommittedOrigin()`.
  if (!was_within_same_document ||
      !::features::IsEnforceSameDocumentOriginInvariantsEnabled()) {
    render_frame_host->browsing_context_state()->SetInsecureRequestPolicy(
        params.insecure_request_policy);
    render_frame_host->browsing_context_state()->SetInsecureNavigationsSet(
        params.insecure_navigations_set);
  }

  // If the committing URL requires the SiteInstance's site to be assigned,
  // that site assignment should've already happened at ReadyToCommit time. We
  // should never get here with a SiteInstance that doesn't have a site
  // assigned in that case.
  SiteInstanceImpl* site_instance = render_frame_host->GetSiteInstance();
  {
    // We don't want the url_info to live to the end of this function because
    // that could let it outlive the `navigation_request`.
    const UrlInfo& url_info = navigation_request->GetUrlInfo();
    if (!site_instance->HasSite() &&
        SiteInstanceImpl::ShouldAssignSiteForUrlInfo(url_info)) {
      // TODO(alexmos): convert this to a CHECK and remove the fallback call to
      // ConvertToDefaultOrSetSite() after verifying that this doesn't happen in
      // practice.
      NOTREACHED() << "SiteInstance should have already set a site: "
                   << params.url;
    }
  }

  // Need to update MIME type here because it's referred to in
  // UpdateNavigationCommands() called by RendererDidNavigate() to
  // determine whether or not to enable the encoding menu.
  // It's updated only for the main frame. For a subframe,
  // RenderView::UpdateURL does not set params.contents_mime_type.
  // (see http://code.google.com/p/chromium/issues/detail?id=2929 )
  // TODO(jungshik): Add a test for the encoding menu to avoid
  // regressing it again.
  // TODO(nasko): Verify the correctness of the above comment, since some of the
  // code doesn't exist anymore. Also, move this code in the
  // PageTransitionIsMainFrame code block above.
  if (ui::PageTransitionIsMainFrame(params.transition)) {
    render_frame_host->GetPage().SetContentsMimeType(params.contents_mime_type);
  }

  render_frame_host->DidNavigate(params, navigation_request.get(),
                                 was_within_same_document);

  int old_entry_count = controller_.GetEntryCount();
  LoadCommittedDetails details;
  base::TimeTicks start = base::TimeTicks::Now();
  bool did_navigate = controller_.RendererDidNavigate(
      render_frame_host, params, &details, was_within_same_document,
      was_on_initial_empty_document,
      previous_document_history_intervention_activation, caused_by_ad,
      navigation_request.get());
  if (!was_within_same_document) {
    base::UmaHistogramTimes(
        base::StrCat(
            {"Navigation.RendererDidNavigateTime.",
             render_frame_host->GetParent() ? "Subframe" : "MainFrame"}),
        base::TimeTicks::Now() - start);
  }

  // Update the RenderFrameHost's last committed FrameNavigationEntry, to have a
  // record of it in rare cases where the last committed NavigationEntry may not
  // agree. Always update this even if the FrameNavigationEntry is null after
  // RendererDidNavigate, to ensure that a stale copy is not kept around.
  // TODO(crbug.com/40467594): Eliminate cases where the
  // FrameNavigationEntry can be null after RendererDidNavigate.
  // TODO(crbug.com/40217743): Merge this with
  // RenderFrameHostImpl::DidNavigate if that can be moved after
  // RendererDidNavigate, allowing us to avoid duplicating the URL and origin in
  // RenderFrameHost.
  FrameNavigationEntry* frame_entry = nullptr;
  if (controller_.GetLastCommittedEntry()) {
    frame_entry =
        controller_.GetLastCommittedEntry()->GetFrameEntry(frame_tree_node);
  }
  render_frame_host->set_last_committed_frame_entry(frame_entry);

  // If the history length and/or index changed, update other renderers in the
  // FrameTree.
  if (old_entry_count != controller_.GetEntryCount() ||
      details.previous_entry_index !=
          controller_.GetLastCommittedEntryIndex()) {
    int history_index = controller_.GetLastCommittedEntryIndex();
    int history_count = controller_.GetEntryCount();
    frame_tree.root()->render_manager()->ExecutePageBroadcastMethod(
        [history_index, history_count](RenderViewHostImpl* rvh) {
          if (auto& broadcast = rvh->GetAssociatedPageBroadcast()) {
            broadcast->SetHistoryIndexAndLength(history_index, history_count);
          }
        },
        site_instance->group());
  }

  // If this was the navigation of a top-level frame to another browsing context
  // group, update the browsing context group in all the renderers that have a
  // representation of this page. Do not update the page in the main frame's own
  // process, as it was already updated during commit.
  // TODO(crbug.com/40268712): See if that can be consolidated with other
  // similar IPCs.
  if (render_frame_host->is_main_frame() &&
      navigation_request->browsing_context_group_swap().ShouldSwap()) {
    SiteInstanceImpl* final_site_instance =
        render_frame_host->GetSiteInstance();
    base::UnguessableToken browsing_context_group_token =
        final_site_instance->browsing_instance_token();
    frame_tree.root()->render_manager()->ExecutePageBroadcastMethod(
        [&browsing_context_group_token](RenderViewHostImpl* rvh) {
          if (auto& broadcast = rvh->GetAssociatedPageBroadcast()) {
            broadcast->UpdatePageBrowsingContextGroup(
                browsing_context_group_token);
          }
        },
        final_site_instance->group());
  }

  // Store some information for recording WebPlatform security metrics. These
  // metrics depends on information present in the NavigationRequest. However
  // they must be recorded after the NavigationRequest has been destroyed and
  // DidFinishNavigation was called, otherwise they will not be properly
  // attributed to the right page.
  bool has_embedding_control = HasEmbeddingControl(navigation_request.get());
  bool is_error_page = navigation_request->IsErrorPage();
  const GURL original_request_url = navigation_request->GetOriginalRequestURL();

  // Get the list of web features that the navigating document made use of
  // before it could commit. We attribute these to the new document once it
  // has committed.
  std::vector<blink::mojom::WebFeature> web_features =
      navigation_request->TakeWebFeaturesToLog();

  // Navigations that activate an existing bfcached or prerendered document do
  // not create a new document.
  bool did_create_new_document =
      !navigation_request->IsPageActivation() && !was_within_same_document;

  // Send notification about committed provisional loads. This notification is
  // different from the NAV_ENTRY_COMMITTED notification which doesn't include
  // the actual URL navigated to.
  DCHECK(delegate_);
  DCHECK_EQ(!render_frame_host->GetParent(),
            did_navigate ? details.is_main_frame : false);
  navigation_request->DidCommitNavigation(params, did_navigate,
                                          details.did_replace_entry,
                                          details.previous_main_frame_url);

  // Dispatch PrimaryPageChanged notification when a main frame
  // non-same-document navigation changes the current Page in the FrameTree.
  //
  // We do this here to ensure that this navigation has updated all relevant
  // properties of RenderFrameHost / Page / Navigation Controller / Navigation
  // Request (e.g. `RenderFrameHost::GetLastCommittedURL`,
  // `NavigationRequest::GetHttpStatusCode`) before notifying the observers.
  // TODO(crbug.com/40207280): Don't dispatch PrimaryPageChanged for initial
  // empty document navigations.
  if (!was_within_same_document && render_frame_host->is_main_frame()) {
    render_frame_host->GetPage().NotifyPageBecameCurrent();

    // Finally reset the `navigation_request` after navigation commit and all
    // NavigationRequest usages.
    navigation_request.reset();
  }

  if (did_create_new_document) {
    RecordWebPlatformSecurityMetrics(render_frame_host, has_embedding_control,
                                     is_error_page);
    RecordMetrics(*render_frame_host, web_features);
  }

  if (!did_navigate)
    return;  // No navigation happened.

  // DO NOT ADD MORE STUFF TO THIS FUNCTION! Your component should either listen
  // for the appropriate notification (best) or you can add it to
  // DidNavigateMainFramePostCommit / DidNavigateAnyFramePostCommit (only if
  // necessary, please).

  // TODO(carlosk): Move this out.
  RecordNavigationMetrics(details, params, site_instance, original_request_url);

  // Now that something has committed, we don't need to track whether the
  // initial page has been accessed.
  frame_tree.ResetHasAccessedInitialMainDocument();

  // Run post-commit tasks.
  if (details.is_main_frame)
    delegate_->DidNavigateMainFramePostCommit(render_frame_host, details);

  delegate_->DidNavigateAnyFramePostCommit(render_frame_host, details);
}

void Navigator::Navigate(std::unique_ptr<NavigationRequest> request,
                         ReloadType reload_type) {
  TRACE_EVENT0("browser,navigation", "Navigator::Navigate");
  TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(
      "navigation,rail", "NavigationTiming navigationStart",
      TRACE_EVENT_SCOPE_GLOBAL, request->common_params().navigation_start);

  FrameTreeNode* frame_tree_node = request->frame_tree_node();
  DCHECK_EQ(&(frame_tree_node->frame_tree()), &controller_.frame_tree());

  //  TODO(crbug.com/40496584):Resolved an issue where creating RPHI would cause
  //  a crash when the browser context was shut down. We are actively exploring
  //  the appropriate long-term solution. Please remove this condition once the
  //  final fix is implemented.
  if (controller_.GetBrowserContext()->ShutdownStarted()) {
    request->set_navigation_discard_reason(
        NavigationDiscardReason::kNeverStarted);
    return;
  }

  // Ignore potentially duplicated navigations, where the new navigation has the
  // same params and details as the current ongoing navigations. These
  // navigations are likely triggered unintentionally (e.g. due to double
  // clicks).
  NavigationRequest* ongoing_navigation_request =
      frame_tree_node->navigation_request();
  bool is_duplicate_navigation = false;
  bool start_diff_under_threshold = false;
  base::TimeDelta nav_start_diff;
  bool is_on_target_origin =
      GetContentClient()->IsUrlInIgnoreDuplicateNavsOrigins(request->GetURL());
  if (ongoing_navigation_request &&
      ongoing_navigation_request->IsRendererInitiated() ==
          request->IsRendererInitiated() &&
      request->GetURL() == ongoing_navigation_request->GetURL() &&
      request->GetURL().SchemeIsHTTPOrHTTPS() &&
      request->common_params().method == "GET" &&
      ongoing_navigation_request->common_params().method == "GET" &&
      request->GetInitiatorFrameToken() ==
          ongoing_navigation_request->GetInitiatorFrameToken() &&
      request->common_params().initiator_origin ==
          ongoing_navigation_request->common_params().initiator_origin &&
      request->common_params().has_possibly_filtered_user_gesture ==
          ongoing_navigation_request->common_params()
              .has_possibly_filtered_user_gesture &&
      request->common_params().should_replace_current_entry ==
          ongoing_navigation_request->common_params()
              .should_replace_current_entry &&
      request->GetNavigationEntryOffset() ==
          ongoing_navigation_request->GetNavigationEntryOffset() &&
      request->GetReloadType() == ongoing_navigation_request->GetReloadType() &&
      request->GetRestoreType() ==
          ongoing_navigation_request->GetRestoreType() &&
      request->common_params().referrer ==
          ongoing_navigation_request->common_params().referrer &&
      request->common_params().transition ==
          ongoing_navigation_request->common_params().transition) {
    // Note: The browser-initiated duplicate navigation cookie check differs
    // from the renderer-initiated check. Since browser-initiated navigations
    // don't pose cross-site leak risks, we can check all cookie changes here
    // (including HttpOnly cookie and cross-document).
    DuplicateNavsCookieStatus cookie_status;
    if (!ongoing_navigation_request->HasCookieChangeListener()) {
      cookie_status = DuplicateNavsCookieStatus::kNoListener;
      is_duplicate_navigation = true;
    } else if (ongoing_navigation_request->DidCookiesChangeAfterStart(
                   /*exclude_http_only=*/false)) {
      cookie_status = DuplicateNavsCookieStatus::kCookiesChanged;
    } else {
      cookie_status = DuplicateNavsCookieStatus::kCookiesNotChanged;
      is_duplicate_navigation = true;
    }
    base::UmaHistogramEnumeration(
        "Navigation.BrowserInitiated.DuplicateNavCookieStatus", cookie_status);
    nav_start_diff =
        (request->common_params().navigation_start -
         ongoing_navigation_request->common_params().navigation_start);
    start_diff_under_threshold =
        nav_start_diff <= GetContentClient()->GetIgnoreDuplicateNavsThreshold();
    if (start_diff_under_threshold) {
      base::UmaHistogramEnumeration(
          "Navigation.BrowserInitiated.DuplicateNavCookieStatus.UnderThreshold",
          cookie_status);
      if (is_on_target_origin) {
        base::UmaHistogramEnumeration(
            "Navigation.BrowserInitiated.DuplicateNavCookieStatus."
            "UnderThreshold.OnTargetOrigins",
            cookie_status);
      }
    }
  }
  base::UmaHistogramBoolean(
      "Navigation.BrowserInitiated.IsDuplicateWithoutThresholdCheck2",
      is_duplicate_navigation);
  if (is_on_target_origin) {
    base::UmaHistogramBoolean(
        "Navigation.BrowserInitiated.IsDuplicateWithoutThresholdCheck2."
        "OnTargetOrigins",
        is_duplicate_navigation);
  }
  if (is_duplicate_navigation) {
    // The navigation is similar to a previous navigation. Check if it's started
    // close enough to the start of the previous navigation, in which case we
    // can just ignore the new navigation and keep the previous navigation.
    base::UmaHistogramBoolean(
        "Navigation.BrowserInitiated.DuplicateNavIsUnderThreshold2",
        start_diff_under_threshold);
    base::UmaHistogramTimes(
        "Navigation.BrowserInitiated.DuplicateNavStartTimeDiff2",
        nav_start_diff);
    if (is_on_target_origin) {
      base::UmaHistogramBoolean(
          "Navigation.BrowserInitiated.DuplicateNavIsUnderThreshold2."
          "OnTargetOrigins",
          start_diff_under_threshold);
      base::UmaHistogramTimes(
          "Navigation.BrowserInitiated.DuplicateNavStartTimeDiff2."
          "OnTargetOrigins",
          nav_start_diff);
    }
    if (!request->IsRendererInitiated()) {
      const auto& new_input_start = request->common_params().input_start;
      const auto& old_input_start =
          ongoing_navigation_request->common_params().input_start;
      blink::InputStartPresence presence;
      if (new_input_start.is_null() && old_input_start.is_null()) {
        presence = blink::InputStartPresence::kNone;
      } else if (new_input_start.is_null()) {
        presence = blink::InputStartPresence::kOnlyOld;
      } else if (old_input_start.is_null()) {
        presence = blink::InputStartPresence::kOnlyNew;
      } else {
        presence = blink::InputStartPresence::kBoth;
      }
      base::UmaHistogramEnumeration(
          "Navigation.BrowserInitiated.DuplicateNavigationInputStartPresence2",
          presence);
      if (presence == blink::InputStartPresence::kBoth) {
        const base::TimeDelta input_diff = new_input_start - old_input_start;
        base::UmaHistogramTimes(
            "Navigation.BrowserInitiated.DuplicateNavInputTimeDiff2",
            input_diff);
        if (is_on_target_origin) {
          base::UmaHistogramTimes(
              "Navigation.BrowserInitiated.DuplicateNavInputTimeDiff2."
              "OnTargetOrigins",
              input_diff);
        }
      }
    }
    if (start_diff_under_threshold &&
        GetContentClient()->ShouldIgnoreDuplicateNavs(
            request->GetURL(), request->IsRendererInitiated())) {
      request->set_navigation_discard_reason(
          NavigationDiscardReason::kNeverStarted);
      DVLOG(0) << "Ignoring duplicate navigation to "
               << request->common_params().url
               << " due to the short interval since the previous one.";
      ongoing_navigation_request->DidIgnoreDuplicateNavigation();
      return;
    } else {
      ongoing_navigation_request->set_navigation_discard_reason(
          NavigationDiscardReason::kNewDuplicateNavigation);
    }
  }

  metrics_data_ = std::make_unique<NavigationMetricsData>(
      request->common_params().navigation_start, request->common_params().url,
      GetPageUkmSourceId(*frame_tree_node->current_frame_host()),
      true /* is_browser_initiated_before_unload */);

  // Check if the BeforeUnload event needs to execute before assigning the
  // NavigationRequest to the FrameTreeNode. Assigning it to the FrameTreeNode
  // has the side effect of initializing the current RenderFrameHost, which will
  // return that it should execute the BeforeUnload event (even though we don't
  // need to wait for it in the case of a brand new RenderFrameHost).
  //
  // We don't want to dispatch a beforeunload handler if
  // is_history_navigation_in_new_child is true. This indicates a newly created
  // child frame which does not have a beforeunload handler.
  //
  // We also don't want to dispatch a beforeunload handler if the browser is
  // forcibly navigating a frame to an error page, because the renderer should
  // have no chance to respond before that occurs.
  // TODO(crbug.com/406729265): LoadPostCommitErrorPage() does not initiate a
  // navigation via Navigator::Navigate(). We should fix that, so that
  // post-commit error page navigations don't bypass other important checks in
  // this function.
  const bool should_dispatch_beforeunload =
      !NavigationTypeUtils::IsSameDocument(
          request->common_params().navigation_type) &&
      !request->common_params().is_history_navigation_in_new_child_frame &&
      frame_tree_node->current_frame_host()->ShouldDispatchBeforeUnload(
          false /* check_subframes_only */) &&
      request->browser_initiated_error_navigation_type() ==
          NavigationRequest::BrowserInitiatedErrorNavigationType::kNone;

  base::UmaHistogramBoolean(
      "Navigation.BrowserInitiated.ShouldDispatchBeforeUnload",
      should_dispatch_beforeunload);

  int nav_entry_id = request->nav_entry_id();
  bool is_pending_entry =
      controller_.GetPendingEntry() &&
      (nav_entry_id == controller_.GetPendingEntry()->GetUniqueID());
  frame_tree_node->TakeNavigationRequest(std::move(request));
  DCHECK(frame_tree_node->navigation_request());

  // Have the current renderer execute its beforeunload event if needed. If it
  // is not needed then NavigationRequest::BeginNavigation should be directly
  // called instead.
  if (should_dispatch_beforeunload) {
    frame_tree_node->navigation_request()->WillStartBeforeUnload();
    frame_tree_node->current_frame_host()->DispatchBeforeUnload(
        RenderFrameHostImpl::BeforeUnloadType::BROWSER_INITIATED_NAVIGATION,
        reload_type != ReloadType::NONE);
  } else {
    frame_tree_node->navigation_request()->BeginNavigation();
    // WARNING: The NavigationRequest might have been destroyed in
    // BeginNavigation(). Do not use |frame_tree_node->navigation_request()|
    // after this point without null checking it first.
  }

  // Make sure no code called via RFH::Navigate clears the pending entry.
  if (is_pending_entry)
    CHECK_EQ(nav_entry_id, controller_.GetPendingEntry()->GetUniqueID());
}

void Navigator::RequestOpenURL(
    RenderFrameHostImpl* render_frame_host,
    const GURL& url,
    const blink::LocalFrameToken* initiator_frame_token,
    int initiator_process_id,
    const std::optional<url::Origin>& initiator_origin,
    const std::optional<GURL>& initiator_base_url,
    scoped_refptr<InitiatorNavigationState> initiator_navigation_state,
    const scoped_refptr<network::ResourceRequestBody>& post_body,
    const std::string& extra_headers,
    const Referrer& referrer,
    WindowOpenDisposition disposition,
    bool should_replace_current_entry,
    bool user_gesture,
    blink::mojom::TriggeringEventInfo triggering_event_info,
    const std::string& href_translate,
    scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory,
    bool has_rel_opener,
    bool started_by_ad) {
  // Note: This can be called for subframes (even when OOPIFs are not possible)
  // if the disposition calls for a different window.

  // Only the current RenderFrameHost should be sending an OpenURL request.
  // Pending RenderFrameHost should know where it is navigating and pending
  // deletion RenderFrameHost shouldn't be trying to navigate.
  if (render_frame_host !=
      render_frame_host->frame_tree_node()->current_frame_host()) {
    return;
  }

  SiteInstance* current_site_instance = render_frame_host->GetSiteInstance();

  // TODO(creis): Pass the redirect_chain into this method to support client
  // redirects.  http://crbug.com/311721.
  std::vector<GURL> redirect_chain;

  FrameTreeNodeId frame_tree_node_id;

  // Send the navigation to the current FrameTreeNode if it's destined for a
  // subframe in the current tab.  We'll assume it's for the main frame
  // (possibly of a new or different WebContents) otherwise.
  if (disposition == WindowOpenDisposition::CURRENT_TAB &&
      render_frame_host->GetParentOrOuterDocument()) {
    frame_tree_node_id =
        render_frame_host->frame_tree_node()->frame_tree_node_id();
  }

  // Prerendering frames need to have an FTN id set, so OpenURL() can find
  // the correct frame tree for the navigation. Due to the above logic, that
  // means this function currently can't be called for prerendering main frames.
  DCHECK(render_frame_host->lifecycle_state() !=
             RenderFrameHostImpl::LifecycleStateImpl::kPrerendering ||
         frame_tree_node_id);

  OpenURLParams params(url, referrer, frame_tree_node_id, disposition,
                       ui::PAGE_TRANSITION_LINK,
                       true /* is_renderer_initiated */);
  params.post_data = post_body;
  params.extra_headers = extra_headers;
  if (redirect_chain.size() > 0)
    params.redirect_chain = redirect_chain;
  params.should_replace_current_entry = should_replace_current_entry;
  params.user_gesture = user_gesture;
  params.triggering_event_info = triggering_event_info;
  params.initiator_origin = initiator_origin;
  params.initiator_base_url = initiator_base_url;
  params.initiator_frame_token = base::OptionalFromPtr(initiator_frame_token);
  params.initiator_process_id = initiator_process_id;
  params.initiator_navigation_state = initiator_navigation_state;
  params.started_by_ad = started_by_ad;

  // RequestOpenURL is used only for local frames, so we can get here only if
  // the navigation is initiated by a frame in the same SiteInstance as this
  // frame.  Note that navigations on RenderFrameProxies do not use
  // RequestOpenURL and go through NavigateFromFrameProxy instead.
  params.source_site_instance = current_site_instance;

  params.source_render_frame_id = render_frame_host->GetRoutingID();
  params.source_render_process_id =
      render_frame_host->GetProcess()->GetDeprecatedID();

  if (WebUI* web_ui = render_frame_host->web_ui()) {
    // Note that we hide the referrer for Web UI pages. We don't really want
    // web sites to see a referrer of "chrome://blah" (and some chrome: URLs
    // might have search terms or other stuff we don't want to send to the
    // site), so we send no referrer.
    params.referrer = Referrer();

    // Navigations in trusted Web UI pages count as browser-initiated
    // navigations.
    if (web_ui->GetController()->GetTrustPolicy() ==
        WebUIController::TrustPolicy::kTrusted) {
      params.is_renderer_initiated = false;
    }
  }

  params.blob_url_loader_factory = std::move(blob_url_loader_factory);
  params.href_translate = href_translate;
  params.has_rel_opener = has_rel_opener;

  delegate_->OpenURL(params, /*navigation_handle_callback=*/{});
}

void Navigator::NavigateFromFrameProxy(
    RenderFrameHostImpl* render_frame_host,
    const GURL& url,
    const blink::LocalFrameToken* initiator_frame_token,
    ChildProcessId initiator_process_id,
    const url::Origin& initiator_origin,
    const std::optional<GURL>& initiator_base_url,
    scoped_refptr<InitiatorNavigationState> initiator_navigation_state,
    const Referrer& referrer,
    ui::PageTransition page_transition,
    bool should_replace_current_entry,
    blink::NavigationDownloadPolicy download_policy,
    const std::string& method,
    scoped_refptr<network::ResourceRequestBody> post_body,
    const std::string& extra_headers,
    scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory,
    network::mojom::SourceLocationPtr source_location,
    bool has_user_gesture,
    bool is_form_submission,
    bool started_by_ad,
    base::TimeTicks actual_navigation_start_time,
    base::TimeTicks navigation_start_time,
    bool is_embedder_initiated_fenced_frame_navigation,
    bool is_unfenced_top_navigation,
    bool force_new_browsing_instance,
    bool is_container_initiated,
    bool has_rel_opener) {
  // |method != "POST"| should imply absence of |post_body|.
  if (method != "POST" && post_body) {
    NOTREACHED();
  }

  // Allow the delegate to cancel the cross-process navigation.
  // With MPArch there may be multiple main frames and so is_main_frame should
  // not be used to identify outermost main frames.
  if (!delegate_->ShouldAllowRendererInitiatedCrossProcessNavigation(
          render_frame_host, render_frame_host->IsOutermostMainFrame())) {
    return;
  }

  // TODO(creis): Determine if this transfer started as a browser-initiated
  // navigation.  See https://crbug.com/495161.
  bool is_renderer_initiated = true;
  Referrer referrer_to_use(referrer);
  if (WebUI* web_ui = render_frame_host->web_ui()) {
    // Note that we hide the referrer for Web UI pages. We don't really want
    // web sites to see a referrer of "chrome://blah" (and some chrome: URLs
    // might have search terms or other stuff we don't want to send to the
    // site), so we send no referrer.
    referrer_to_use = Referrer();

    // Navigations in trusted Web UI pages count as browser-initiated
    // navigations.
    if (web_ui->GetController()->GetTrustPolicy() ==
        WebUIController::TrustPolicy::kTrusted) {
      is_renderer_initiated = false;
    }
  }

  if (is_renderer_initiated &&
      ShouldIgnoreIncomingRendererRequest(
          render_frame_host->frame_tree_node()->navigation_request(),
          has_user_gesture)) {
    return;
  }

  // Only active and prerendered documents are allowed to start navigation in
  // their frame.
  if (render_frame_host->lifecycle_state() !=
      RenderFrameHostImpl::LifecycleStateImpl::kPrerendering) {
    // If this is reached in case the RenderFrameHost is in BackForwardCache
    // evict the document from BackForwardCache.
    if (render_frame_host->IsInactiveAndDisallowActivation(
            DisallowActivationReasonId::kBeginNavigation)) {
      return;
    }
  }

  controller_.NavigateFromFrameProxy(
      render_frame_host, url, initiator_frame_token, initiator_process_id,
      initiator_origin, initiator_base_url, is_renderer_initiated,
      initiator_navigation_state, referrer_to_use, page_transition,
      should_replace_current_entry, download_policy, method, post_body,
      extra_headers, std::move(source_location),
      std::move(blob_url_loader_factory), is_form_submission, has_user_gesture,
      started_by_ad, actual_navigation_start_time, navigation_start_time,
      is_embedder_initiated_fenced_frame_navigation, is_unfenced_top_navigation,
      force_new_browsing_instance, is_container_initiated, has_rel_opener);
}

void Navigator::BeforeUnloadCompleted(FrameTreeNode* frame_tree_node,
                                      bool proceed,
                                      const base::TimeTicks& proceed_time,
                                      bool for_legacy,
                                      bool showed_dialog) {
  DCHECK(frame_tree_node);

  NavigationRequest* navigation_request = frame_tree_node->navigation_request();

  // The NavigationRequest may have been canceled while the renderer was
  // executing the BeforeUnload event.
  if (!navigation_request)
    return;

  // If the user chose not to proceed, cancel the ongoing navigation.
  // Note: it might be a new navigation, and not the one that triggered the
  // sending of the BeforeUnload IPC in the first place. However, the
  // BeforeUnload where the user asked not to proceed will have taken place
  // after the navigation started. The last user input should be respected, and
  // the navigation cancelled anyway.
  if (!proceed) {
    CancelNavigation(frame_tree_node,
                     NavigationDiscardReason::kExplicitCancellation);
    return;
  }

  // The browser-initiated NavigationRequest that triggered the sending of the
  // BeforeUnload IPC might have been replaced by a renderer-initiated one while
  // the BeforeUnload event executed in the renderer. In that case, the request
  // will already have begun, so there is no need to start it again.
  if (navigation_request->state() >
      NavigationRequest::WAITING_FOR_RENDERER_RESPONSE) {
    DCHECK(navigation_request->from_begin_navigation());
    return;
  }

  // Update the navigation start: it should be when it was determined that the
  // navigation will proceed.
  navigation_request->UpdateNavigationStartTime(proceed_time, for_legacy,
                                                showed_dialog);

  DCHECK_EQ(NavigationRequest::WAITING_FOR_RENDERER_RESPONSE,
            navigation_request->state());

  // Send the request to the IO thread.
  navigation_request->BeginNavigation();
  // DO NOT USE |navigation_request| BEYOND THIS POINT. It might have been
  // destroyed in BeginNavigation().
  // See https://crbug.com/770157.
}

void Navigator::OnBeginNavigation(
    FrameTreeNode* frame_tree_node,
    blink::mojom::CommonNavigationParamsPtr common_params,
    blink::mojom::BeginNavigationParamsPtr begin_params,
    scoped_refptr<network::SharedURLLoaderFactory> blob_url_loader_factory,
    mojo::PendingAssociatedRemote<mojom::NavigationClient> navigation_client,
    scoped_refptr<PrefetchedSignedExchangeCache>
        prefetched_signed_exchange_cache,
    ChildProcessId initiator_process_id,
    mojo::PendingReceiver<mojom::NavigationRendererCancellationListener>
        renderer_cancellation_listener,
    mojo::PendingReceiver<
        mojom::NavigationRendererIgnoreDuplicateNavigationListener>
        renderer_ignore_duplicate_navigation_listener,
    mojo::PendingReceiver<blink::mojom::NavigationResumeDeferredCommitListener>
        deferred_commit_resume_listener,
    scoped_refptr<InitiatorNavigationState> initiator_navigation_state) {
  TRACE_EVENT0("navigation", "Navigator::OnBeginNavigation");

  if (common_params->is_history_navigation_in_new_child_frame) {
    // Try to find a FrameNavigationEntry that matches this frame instead, based
    // on the frame's unique name.  If this can't be found, fall back to the
    // default path below.

    // |initiator_frame_token| is non-null here because a navigation in a new
    // subframe always begins with renderer action (i.e., an HTML element being
    // inserted into the DOM), so it is always renderer-initiated.
    // Anyway validating |initiator_frame_token| here because it's from a
    // renderer process.
    DCHECK(begin_params->initiator_frame_token);
    if (begin_params->initiator_frame_token &&
        frame_tree_node->navigator().StartHistoryNavigationInNewSubframe(
            frame_tree_node->current_frame_host(), &navigation_client,
            *begin_params->initiator_frame_token, initiator_process_id,
            initiator_navigation_state,
            common_params->actual_navigation_start)) {
      return;
    }
  }

  NavigationRequest* ongoing_navigation_request =
      frame_tree_node->navigation_request();

  // Client redirects during the initial history navigation of a child frame
  // should take precedence over the history navigation (despite being renderer-
  // initiated).  See https://crbug.com/348447 and https://crbug.com/691168.
  if (ongoing_navigation_request &&
      ongoing_navigation_request->common_params()
          .is_history_navigation_in_new_child_frame) {
    // Preemptively clear this local pointer before deleting the request.
    ongoing_navigation_request = nullptr;
    frame_tree_node->ResetNavigationRequest(
        NavigationDiscardReason::kNewOtherNavigationRendererInitiated);
  }

  // Verify this navigation has precedence.
  if (ShouldIgnoreIncomingRendererRequest(
          ongoing_navigation_request,
          common_params->has_possibly_filtered_user_gesture)) {
    return;
  }

  // Compute this ahead of creating the NavigationEntry, since it is needed both
  // there and in CreateRendererInitiated.
  const bool override_user_agent =
      delegate_->ShouldOverrideUserAgentForRendererInitiatedNavigation();

  NavigationEntryImpl* navigation_entry =
      GetNavigationEntryForRendererInitiatedNavigation(
          *common_params, frame_tree_node, override_user_agent);

  frame_tree_node->TakeNavigationRequest(
      NavigationRequest::CreateRendererInitiated(
          frame_tree_node, navigation_entry, std::move(common_params),
          std::move(begin_params), controller_.GetLastCommittedEntryIndex(),
          controller_.GetEntryCount(), override_user_agent,
          std::move(blob_url_loader_factory), std::move(navigation_client),
          std::move(prefetched_signed_exchange_cache),
          std::move(renderer_cancellation_listener),
          std::move(renderer_ignore_duplicate_navigation_listener),
          std::move(deferred_commit_resume_listener),
          initiator_navigation_state));
  NavigationRequest* navigation_request = frame_tree_node->navigation_request();

  metrics_data_ = std::make_unique<NavigationMetricsData>(
      navigation_request->common_params().navigation_start,
      navigation_request->common_params().url,
      GetPageUkmSourceId(*frame_tree_node->current_frame_host()),
      false /* is_browser_initiated_before_unload */);

  LogRendererInitiatedBeforeUnloadTime(
      navigation_request->begin_params().before_unload_start,
      navigation_request->begin_params().before_unload_end);

  // This frame has already run beforeunload before it sent this IPC.  See if
  // any of its cross-process subframes also need to run beforeunload.  If so,
  // delay the navigation until beforeunload completion callbacks are invoked on
  // those frames.
  DCHECK(!NavigationTypeUtils::IsSameDocument(
      navigation_request->common_params().navigation_type));
  const bool should_dispatch_beforeunload =
      frame_tree_node->current_frame_host()->ShouldDispatchBeforeUnload(
          true /* check_subframes_only */);
  base::UmaHistogramBoolean(
      "Navigation.RendererInitiated.ShouldDispatchBeforeUnload",
      should_dispatch_beforeunload);
  if (should_dispatch_beforeunload) {
    frame_tree_node->navigation_request()->WillStartBeforeUnload();
    frame_tree_node->current_frame_host()->DispatchBeforeUnload(
        RenderFrameHostImpl::BeforeUnloadType::RENDERER_INITIATED_NAVIGATION,
        NavigationTypeUtils::IsReload(
            navigation_request->common_params().navigation_type));
    return;
  }

  // For main frames, NavigationHandle will be created after the call to
  // |DidStartMainFrameNavigation|, so it receives the most up to date pending
  // entry from the NavigationController.
  navigation_request->BeginNavigation();
  // DO NOT USE |navigation_request| BEYOND THIS POINT. It might have been
  // destroyed in BeginNavigation().
  // See https://crbug.com/770157.
}

void Navigator::RestartNavigationAsCrossDocument(
    std::unique_ptr<NavigationRequest> navigation_request) {
  FrameTreeNode* frame_tree_node = navigation_request->frame_tree_node();
  // Don't restart the navigation if there is already another ongoing navigation
  // in the FrameTreeNode.
  if (frame_tree_node->navigation_request())
    return;

  navigation_request->ResetForCrossDocumentRestart();
  frame_tree_node->TakeNavigationRequest(std::move(navigation_request));
  frame_tree_node->navigation_request()->BeginNavigation();
  // DO NOT USE THE NAVIGATION REQUEST BEYOND THIS POINT. It might have been
  // destroyed in BeginNavigation().
  // See https://crbug.com/770157.
}

void Navigator::CancelNavigation(FrameTreeNode* frame_tree_node,
                                 NavigationDiscardReason reason) {
  if (frame_tree_node->navigation_request())
    frame_tree_node->navigation_request()->set_net_error(net::ERR_ABORTED);
  frame_tree_node->ResetNavigationRequest(reason);
  if (frame_tree_node->IsMainFrame())
    metrics_data_.reset();
}

void Navigator::LogCommitNavigationSent() {
  if (!metrics_data_) {
    return;
  }

  metrics_data_->commit_navigation_sent_ = base::TimeTicks::Now();
}

void Navigator::LogBeforeUnloadTime(
    base::TimeTicks renderer_before_unload_start_time,
    base::TimeTicks renderer_before_unload_end_time,
    base::TimeTicks before_unload_sent_time,
    bool for_legacy) {
  if (!metrics_data_) {
    return;
  }

  // LogBeforeUnloadTime is called once for each cross-process frame. Once all
  // beforeunloads complete, the timestamps in navigation_data will be the
  // timestamps of the beforeunload that blocked the navigation the longest.
  // `for_legacy` indicates this is being called as the result of a PostTask(),
  // which did not go to the renderer so that the times do not need to be
  // adjusted.
  if (!base::TimeTicks::IsConsistentAcrossProcesses() && !for_legacy) {
    // These timestamps come directly from the renderer so they might need to be
    // converted to local time stamps.
    blink::InterProcessTimeTicksConverter converter(
        blink::LocalTimeTicks::FromTimeTicks(before_unload_sent_time),
        blink::LocalTimeTicks::FromTimeTicks(base::TimeTicks::Now()),
        blink::RemoteTimeTicks::FromTimeTicks(
            renderer_before_unload_start_time),
        blink::RemoteTimeTicks::FromTimeTicks(renderer_before_unload_end_time));
    blink::LocalTimeTicks converted_renderer_before_unload_start =
        converter.ToLocalTimeTicks(blink::RemoteTimeTicks::FromTimeTicks(
            renderer_before_unload_start_time));
    blink::LocalTimeTicks converted_renderer_before_unload_end =
        converter.ToLocalTimeTicks(blink::RemoteTimeTicks::FromTimeTicks(
            renderer_before_unload_end_time));
    metrics_data_->before_unload_start_ =
        converted_renderer_before_unload_start.ToTimeTicks();
    metrics_data_->before_unload_end_ =
        converted_renderer_before_unload_end.ToTimeTicks();
  } else {
    metrics_data_->before_unload_start_ = renderer_before_unload_start_time;
    metrics_data_->before_unload_end_ = renderer_before_unload_end_time;
  }
  metrics_data_->before_unload_sent_ = before_unload_sent_time;
}

void Navigator::LogRendererInitiatedBeforeUnloadTime(
    base::TimeTicks renderer_before_unload_start_time,
    base::TimeTicks renderer_before_unload_end_time) {
  DCHECK(metrics_data_);

  if (renderer_before_unload_start_time == base::TimeTicks() ||
      renderer_before_unload_end_time == base::TimeTicks())
    return;

  if (!base::TimeTicks::IsConsistentAcrossProcesses()) {
    // These timestamps come directly from the renderer so they might need to be
    // converted to local time stamps. However, since this is
    // renderer-initiated, we don't have a browser-side `local_lower_bound`
    // anchor for the start of the event.
    //
    // `InterProcessTimeTicksConverter` is not applicable here because it
    // requires a two-point anchor (both start and end points on both local and
    // remote processes) to decouple clock skew from communication latency.
    // Without a start anchor (`local_lower_bound`), we cannot calculate the
    // round-trip time or the scaling factor.
    //
    // We instead assume the event finished just before it was received and use
    // the renderer's duration to establish the local timestamps.
    base::TimeTicks now = base::TimeTicks::Now();
    metrics_data_->renderer_before_unload_start_ =
        now -
        (renderer_before_unload_end_time - renderer_before_unload_start_time);
    metrics_data_->renderer_before_unload_end_ = now;
  } else {
    metrics_data_->renderer_before_unload_start_ =
        renderer_before_unload_start_time;
    metrics_data_->renderer_before_unload_end_ =
        renderer_before_unload_end_time;
  }
}

void Navigator::RecordNavigationMetrics(
    const LoadCommittedDetails& details,
    const mojom::DidCommitProvisionalLoadParams& params,
    SiteInstance* site_instance,
    const GURL& original_request_url) {
  DCHECK(site_instance->HasProcess());

  if (!details.is_main_frame || !metrics_data_ ||
      metrics_data_->url_ != original_request_url ||
      metrics_data_->ukm_source_id_ == ukm::kInvalidSourceId) {
    // The source ID will be invalid for prerendered pages. See
    // `GetPageUkmSourceId()`.
    metrics_data_.reset();
    return;
  }

  ukm::builders::Unload builder(metrics_data_->ukm_source_id_);
  base::TimeTicks first_before_unload_start_time;

  if (metrics_data_->is_browser_initiated_before_unload_) {
    if (metrics_data_->before_unload_start_ &&
        metrics_data_->before_unload_end_) {
      first_before_unload_start_time =
          metrics_data_->before_unload_start_.value();
      builder.SetBeforeUnloadDuration(
          (metrics_data_->before_unload_end_.value() -
           metrics_data_->before_unload_start_.value())
              .InMilliseconds());
    }
  } else {
    if (metrics_data_->renderer_before_unload_start_ &&
        metrics_data_->renderer_before_unload_end_) {
      first_before_unload_start_time =
          metrics_data_->renderer_before_unload_start_.value();
      base::TimeDelta before_unload_duration =
          metrics_data_->renderer_before_unload_end_.value() -
          metrics_data_->renderer_before_unload_start_.value();

      // If we had to dispatch beforeunload handlers for OOPIFs from the
      // browser, add those into the beforeunload duration as they contributed
      // to the total beforeunload latency.
      if (metrics_data_->before_unload_sent_) {
        before_unload_duration += metrics_data_->before_unload_end_.value() -
                                  metrics_data_->before_unload_start_.value();
      }
      builder.SetBeforeUnloadDuration(before_unload_duration.InMilliseconds());
    }
  }

  // Records the queuing duration of the beforeunload sent from the browser to
  // the frame that blocked the navigation the longest. This can happen in a
  // renderer or browser initiated navigation and could mean a long queuing time
  // blocked the navigation or a long beforeunload. Records nothing if none were
  // sent.
  if (metrics_data_->before_unload_sent_) {
    builder.SetBeforeUnloadQueueingDuration(
        (metrics_data_->before_unload_start_.value() -
         metrics_data_->before_unload_sent_.value())
            .InMilliseconds());
  }

  // If this is a same-process navigation and we have timestamps for unload
  // durations, fill those metrics out as well.
  if (params.unload_start && params.unload_end &&
      params.commit_navigation_end && metrics_data_->commit_navigation_sent_) {
    base::TimeTicks unload_start = params.unload_start.value();
    base::TimeTicks unload_end = params.unload_end.value();
    // Note: we expect `commit_navigation_end` to be later than `unload_end`.
    // `unload_end` is recorded when the unload handlers finish running, which
    // happens prior to the navigation committing and recording
    // `commit_navigation_end` in this same-process case.
    base::TimeTicks commit_navigation_end =
        params.commit_navigation_end.value();

    if (!base::TimeTicks::IsConsistentAcrossProcesses()) {
      // These timestamps come directly from the renderer so they might need
      // to be converted to local time stamps.
      blink::InterProcessTimeTicksConverter converter(
          blink::LocalTimeTicks::FromTimeTicks(first_before_unload_start_time),
          blink::LocalTimeTicks::FromTimeTicks(base::TimeTicks::Now()),
          blink::RemoteTimeTicks::FromTimeTicks(unload_start),
          blink::RemoteTimeTicks::FromTimeTicks(commit_navigation_end));
      blink::LocalTimeTicks converted_unload_start = converter.ToLocalTimeTicks(
          blink::RemoteTimeTicks::FromTimeTicks(unload_start));
      blink::LocalTimeTicks converted_unload_end = converter.ToLocalTimeTicks(
          blink::RemoteTimeTicks::FromTimeTicks(unload_end));
      blink::LocalTimeTicks converted_commit_navigation_end =
          converter.ToLocalTimeTicks(
              blink::RemoteTimeTicks::FromTimeTicks(commit_navigation_end));
      unload_start = converted_unload_start.ToTimeTicks();
      unload_end = converted_unload_end.ToTimeTicks();
      commit_navigation_end = converted_commit_navigation_end.ToTimeTicks();
    }
    builder.SetUnloadDuration((unload_end - unload_start).InMilliseconds());
    builder.SetUnloadQueueingDuration(
        (unload_start - metrics_data_->commit_navigation_sent_.value())
            .InMilliseconds());
    if (metrics_data_->commit_navigation_sent_) {
      builder.SetBeforeUnloadToCommit_SameProcess(
          (commit_navigation_end - first_before_unload_start_time)
              .InMilliseconds());
    }
  } else if (metrics_data_->commit_navigation_sent_) {
    // The navigation is cross-process and we don't have unload timings as they
    // are run in the old process and don't block the navigation.
    builder.SetBeforeUnloadToCommit_CrossProcess(
        (metrics_data_->commit_navigation_sent_.value() -
         first_before_unload_start_time)
            .InMilliseconds());
  }

  builder.Record(ukm::UkmRecorder::Get());
  metrics_data_.reset();
}

NavigationEntryImpl*
Navigator::GetNavigationEntryForRendererInitiatedNavigation(
    const blink::mojom::CommonNavigationParams& common_params,
    FrameTreeNode* frame_tree_node,
    bool override_user_agent) {
  // With MPArch, there may be multiple main frames, but each one has its own
  // NavigationController. Thus, it's correct to check for NavigationEntries for
  // each main frame, even if one is embedded (e.g., a fenced frame).
  if (!frame_tree_node->IsMainFrame())
    return nullptr;

  // If there is no browser-initiated pending entry for this navigation and it
  // is not for the error URL, create a pending entry and ensure the address bar
  // updates accordingly.  We don't know the referrer or extra headers at this
  // point, but the referrer will be set properly upon commit.  This does not
  // set the SiteInstance for the pending entry, because it may change
  // before the URL commits.
  NavigationEntryImpl* pending_entry = controller_.GetPendingEntry();
  bool has_browser_initiated_pending_entry =
      pending_entry && !pending_entry->is_renderer_initiated();
  if (has_browser_initiated_pending_entry)
    return nullptr;

  // A pending navigation entry is created in OnBeginNavigation(). The renderer
  // sends a provisional load notification after that. We don't want to create
  // a duplicate navigation entry here.
  bool renderer_provisional_load_to_pending_url =
      pending_entry && pending_entry->is_renderer_initiated() &&
      (pending_entry->GetURL() == common_params.url);
  if (renderer_provisional_load_to_pending_url)
    return nullptr;

  // Since GetNavigationEntryForRendererInitiatedNavigation is called from
  // OnBeginNavigation, we can assume that no frame proxies are involved and
  // therefore that |current_site_instance| is also the |source_site_instance|.
  SiteInstance* current_site_instance =
      frame_tree_node->current_frame_host()->GetSiteInstance();
  std::optional<GURL> source_process_site_url = std::nullopt;
  if (current_site_instance && current_site_instance->HasProcess()) {
    source_process_site_url =
        current_site_instance->GetProcess()->GetProcessLock().site_url();
  }
  // If `frame_tree_node` is the outermost main frame, it rewrites a virtual
  // url in order to adjust the original input url if needed. For inner frames
  // such as fenced frames or subframes, they don't rewrite urls as the urls
  // are not input urls by users.
  bool rewrite_virtual_urls = frame_tree_node->IsOutermostMainFrame();
  std::unique_ptr<NavigationEntryImpl> entry =
      NavigationEntryImpl::FromNavigationEntry(
          NavigationControllerImpl::CreateNavigationEntry(
              common_params.url, content::Referrer(),
              common_params.initiator_origin, common_params.initiator_base_url,
              source_process_site_url, ui::PAGE_TRANSITION_LINK,
              true /* is_renderer_initiated */,
              std::string() /* extra_headers */,
              controller_.GetBrowserContext(),
              nullptr /* blob_url_loader_factory */, rewrite_virtual_urls));

  entry->set_reload_type(NavigationRequest::NavigationTypeToReloadType(
      common_params.navigation_type));
  entry->SetIsOverridingUserAgent(override_user_agent);
  controller_.SetPendingEntry(std::move(entry));

  // If the embedder's OverrideNavigationParams flipped this entry's
  // is_renderer_initiated bit to false (e.g., for an NTP navigation that
  // gets overridden to look browser-initiated), the INVALIDATE_TYPE_URL
  // notification in SetPendingEntry was skipped because it is gated on
  // is_renderer_initiated(). Fire it here so the omnibox can reflect the
  // destination URL during the pending navigation, rather than displaying
  // stale text until commit.
  if (!controller_.GetPendingEntry()->is_renderer_initiated()) {
    delegate_->NotifyChangedNavigationState(INVALIDATE_TYPE_URL);
  }

  return controller_.GetPendingEntry();
}

}  // namespace content