Test Predator has given the following results:

Make blink::GlobalEventHandlers a static-only class, not a namespace by tkent@chromium.org
Changed files GlobalEventHandlers.h, with the same CrashedDirectory(third_party/WebKit/Source/core/dom) as TaskRunnerHelper.cpp (in frame#0)
Changed files GlobalEventHandlers.h, with the same CrashedComponent(Blink>DOM) as TaskRunnerHelper.cpp (in frame#0)

@tkent  -- Could you please look into this issue, kindly reassign if it has nothing to do with your changes.

Thank You.

> Changed files GlobalEventHandlers.h, with the same CrashedDirectory(third_party/WebKit/Source/core/dom) as TaskRunnerHelper.cpp (in frame#0)

They are completely unrelated.

TEs, please just add component:Blink to crashes in blink:: namespace. The Blink bug rotation will handle issues with component:Blink.

Predator and CL could not provide any possible suspects.
Using the code search for the file, “TaskRunnerHelper.cpp” assigning to concern owner from GIT blame.
Suspecting Commit#
https://chromium.googlesource.com/chromium/src/+/905a5fd6040cc73a6adaff129faa5bf0b1edfc2a
@nhiroki  -- Could you please look into this issue, kindly reassign if it has nothing to do with your changes.
Thank You.

It looks like the given execution context is null. Let me forward to the owners of TimedCanvasDrawListener (+emircan@,mcasas@).

ClusterFuzz has detected this issue as fixed in range 504594:504637.

Detailed report: https://clusterfuzz.com/testcase?key=5923035088683008

Fuzzer: lcamtuf_cross_fuzz
Job Type: windows_asan_chrome
Platform Id: windows

Crash Type: Null-dereference READ
Crash Address: 0x00000000
Crash State:
  blink::TaskRunnerHelper::Get
  blink::TimedCanvasDrawListener::TimedCanvasDrawListener
  blink::TimedCanvasDrawListener::Create
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=windows_asan_chrome&range=502608:502648
Fixed: https://clusterfuzz.com/revisions?job=windows_asan_chrome&range=504594:504637

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5923035088683008

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 5923035088683008 is verified as fixed, so closing issue as verified.

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