As per the  Issue 780991  owner assigning this issue to @kylixrd.
@kylixrd-- Could you please look into this issue, kindly reassign if it has nothing to do with your changes.
Thanks.

ClusterFuzz has detected this issue as fixed in range 514459:514469.

Detailed report: https://clusterfuzz.com/testcase?key=6165142906863616

Fuzzer: attekett_surku_fuzzer
Job Type: linux_cfi_chrome
Platform Id: linux

Crash Type: Null-dereference
Crash Address: 0x0000000000f8
Crash State:
  FindBarController::FindBarVisibilityChanged
  FindBarHost::OnVisibilityChanged
  FindBarController::ChangeWebContents
  
Sanitizer: cfi (CFI)

Regressed: https://clusterfuzz.com/revisions?job=linux_cfi_chrome&range=513107:513112
Fixed: https://clusterfuzz.com/revisions?job=linux_cfi_chrome&range=514459:514469

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6165142906863616

Additional requirements: Requires Gestures

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.