Tests that browser.Target.setAutoAttach() attaches to window.open targets.
Opened the window
Attached to window, waitingForDebugger=true
Resumed popup window
Popup window URL changed to http://127.0.0.1:8000/inspector-protocol/resources/inspector-protocol-page.html
Navigated the window
Target info changed, new URL is http://127.0.0.1:8000/inspector-protocol/resources/test-page.html
Closed the window
Detached from window