Predator and CL could not provide any possible suspects.
Using Code Search for the file,"HeapPage.h" assigning to concern owner who might be related.

@keishi -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

ClusterFuzz has detected this issue as fixed in range 496287:496302.

Detailed report: https://clusterfuzz.com/testcase?key=6424042507862016

Fuzzer: inferno_layout_test_unmodified
Job Type: linux_debug_content_shell_drt
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  IsValid() in HeapPage.h
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_debug_content_shell_drt&range=473085:473088
Fixed: https://clusterfuzz.com/revisions?job=linux_debug_content_shell_drt&range=496287:496302

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6424042507862016

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 6424042507862016 is verified as fixed, so closing issue as verified.

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