Automatically applying components based on crash stacktrace and information from OWNERS files.

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Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/chromium/src/+/68d8dbc019fd37659252e273ade868aac7a9d8ac (Don't make a LayerTreeFrameSink for a non-visible RenderWidget.).

If this is incorrect, please let us know why and apply the Test-Predator-Wrong-CLs label. If you aren't the correct owner for this issue, please unassign yourself as soon as possible so it can be re-triaged.

This is a racey CHECK, and I think the code should be fixed to deal with this case.

This method is run on a post-task. If the frame was actually detached, then it would be removed from Page and this method would have early outted. Which I assume means it is in kDetaching state, and Frame::Detach() early outted?

https://cs.chromium.org/chromium/src/third_party/blink/renderer/core/frame/frame.cc?rcl=7a0ed6e7db059cc42feb9fc3ad2ac857c0ba31c4&l=89

  // Due to re-entrancy, |this| could have completed detaching already.
  if (!client_)
    return;

Looks like this is hitting the CHECK added for investigating 838348, so this should with diagnosing.

ClusterFuzz has detected this issue as fixed in range 613666:613677.

Detailed report: https://clusterfuzz.com/testcase?key=5122460414115840

Fuzzer: ifratric-browserfuzzer-v3
Job Type: linux_ubsan_chrome
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  main_frame_->IsAttached() in page.cc
  blink::Page::RequestBeginMainFrameNotExpected
  blink::scheduler::MainThreadSchedulerImpl::DispatchRequestBeginMainFrameNotExpec
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_chrome&range=606653:606655
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_chrome&range=613666:613677

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5122460414115840

See https://github.com/google/clusterfuzz-tools for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 5122460414115840 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.