Based on the code search on 'StringImpl.h', kotenkov@: Could this be related to https://codereview.chromium.org/2016223002.

Please help in investigating this further if the change is not related.

Cc'ing haraken@ and yutak@ as the reviewer of the above CL. 

This should not be related, since it is a revert of a CL that was introduced a couple of days earlier and both CLs don't do anything except renaming RELEASE_ASSERTS.
Unfortunately, I don't have access to clusterfuzz, so I cannot se the testcase and investigate it further.

Indeed kotenkov's change has nothing to do with this.

This appears worker-related.

ClusterFuzz has detected this issue as fixed in range 397130:397162.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=4558499862544384

Fuzzer: ochang_domfuzzer
Job Type: linux_tsan_chrome_mp
Platform Id: linux

Crash Type: Data race READ 4
Crash Address: 0x7d2400035dc0
Crash State:
  blink::StringCacheMapTraits::Dispose
  v8::PersistentValueMapBase<WTF::StringImpl*, v8::String, blink::StringCacheMapTr
  blink::StringCache::dispose
  
Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_tsan_chrome_mp&range=396083:396125
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_tsan_chrome_mp&range=397130:397162

Unminimized Testcase: https://cluster-fuzz.appspot.com/download/AMIfv97CHaVVHBdvHLG3O9pyijC7i9EPR08j3FPSW_YbgOg4Vl_gqjnhKE4Wnkj3lcrRr69vBmB9FljwQ2trozx0Vk1YS-qOWdf3pNw9KXcwqjPvsmdOGpID8Lnzv7WGYhysOAbp8eiKhl5tBT79MNjanMnzECW60w


See https://dev.chromium.org/Home/chromium-security/bugs/reproducing-clusterfuzz-bugs 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 is verified as fixed, closing issue.

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