Suspected CL from regression range
https://chromium.googlesource.com/chromium/src/+/7fe94f0a7f3809fd93916c526d067dcb7f2b4ce3
csharrison@, could you please take a look?
Thank you.

ClusterFuzz has detected this issue as fixed in range 450980:451105.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5312659701628928

Fuzzer: inferno_webbot
Job Type: linux_msan_chrome
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  i < size() in Vector.h
  blink::BackgroundHTMLInputStream::invalidateCheckpointsBefore
  blink::BackgroundHTMLParser::startedChunkWithCheckpoint
  
Sanitizer: memory (MSAN)

Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=450553:450625
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=450980:451105

Reproducer Testcase: https://cluster-fuzz.appspot.com/download/AMIfv97D4riUFN1lWMgXjMfHSyWT77A2nWRnplM-vFGX4fKYe7RjK_IPx2laRlM5Su_6bbCPQ6swUg43QIhWp3xb16O0AC3rFt2V3XlYhoTQhkUUGsoVHwICEp9zfsvfYExNxgB33PUVUkrnvwLuSq33OPftHpUsGsyxrDC8TyW8-YNTdRaExcEjyaV5S-BhRW6cog6epHXTD--fgoaeqGJ928-kxuP0Jxr-hxOpxZjuV7Jhy00meQyFtggcLPR5TA2h3tqDaAP7OgnAn6vin9AWxkObcy60mxxUtgkoVS4b8FuJ0wvMtvUjN8cclmmXbFy1JxjfVJ7pnFbAkPw01GIW-HADBo1K_9Zw0ya4FSXVNd3f7YBeBo9jfiO_TR9JM2qnQQVahceeW_CTTNYsrucT_joLbrr9-w?testcase_id=5312659701628928


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 5312659701628928 is verified as fixed, so closing issue.

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