Verify that removal of one of the multiple projects, all of which are associated with the same frame, doesn't lead navigator to discard the frame treenode.



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Adding urls
top
  127.0.0.1:8000
    devtools/resources
      inspected-page.html
  localhost:8080
    LayoutTests/inspector/debugger/foo/bar
      script.js


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Removing contentScripts project
top
  127.0.0.1:8000
    devtools/resources
      inspected-page.html
  localhost:8080
    LayoutTests/inspector/debugger/foo/bar
      script.js