Automatically applying components based on crash stacktrace and information from OWNERS files.

If this is incorrect, please apply the Test-Predator-Wrong-Components label.

Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/chromium/src/+/a46b62e9900f5ac48951f8ad68d9e03eded4cc8d (Create an empty StyleSheetList for moreStyleSheets.).

If this is incorrect, please let us know why and apply the Test-Predator-Wrong-CLs label. If you aren't the correct owner for this issue, please unassign yourself as soon as possible so it can be re-triaged.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9d5d29127490e791084b7727b062fb0cf50d29dd

commit 9d5d29127490e791084b7727b062fb0cf50d29dd
Author: Rune Lillesveen <futhark@chromium.org>
Date: Fri Mar 23 12:11:39 2018

Missing nullptr check for scope in StyleSheetList.

The StyleSheetList for the moreStyleSheets API does not have a
TreeScope which made the named getter crash.

Bug:  823115 
Change-Id: Ibc67ff06d328f9f771cba4e0c74080133e4fcfbb
Reviewed-on: https://chromium-review.googlesource.com/977901
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545411}
[modify] https://crrev.com/9d5d29127490e791084b7727b062fb0cf50d29dd/third_party/WebKit/Source/core/css/StyleSheetList.cpp
[modify] https://crrev.com/9d5d29127490e791084b7727b062fb0cf50d29dd/third_party/WebKit/Source/core/css/StyleSheetListTest.cpp

ClusterFuzz has detected this issue as fixed in range 545408:545411.

Detailed report: https://clusterfuzz.com/testcase?key=5636247473881088

Fuzzer: inferno_layout_test_unmodified
Job Type: linux_ubsan_vptr_content_shell_drt
Platform Id: linux

Crash Type: Null-dereference READ
Crash Address: 0x000000000000
Crash State:
  blink::TreeScope::getElementById
  blink::StyleSheetList::GetNamedItem
  blink::StyleSheetList::AnonymousNamedGetter
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=543652:543654
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=545408:545411

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5636247473881088

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 5636247473881088 is verified as fixed, so closing issue as verified.

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