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/+/2d21d004fa5157a1c4409b19e2f808001d026304 ([Squad] Make pseudo element creation not rely on layout tree.).

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/+/4953b70f39f00c5be23b84aade0084c025cc709b

commit 4953b70f39f00c5be23b84aade0084c025cc709b
Author: Rune Lillesveen <futhark@chromium.org>
Date: Mon Jul 23 20:42:28 2018

[Squad] Re-add null check for layout parent.

Because of issue 831568, we may end up trying to generate pseudo
elements for element outside the flat tree if we did a getComputedStyle
for all non-flat-tree ancestors and then triggered style invalidation of
the pseudo element's originating element.

This is not a new issue, but [1] boldly tried to make the if-test for a
layout parent a DCHECK. This CL is effectively reverting that change.

This should ultimately be fixed by fixing 831568 and re-introduce DCHECK
instead of the if-test.

[1] https://crrev.com/86f6eefc70ed2aa46969754e207198bd6917ee33

Bug:  862098 , 831568
Change-Id: Id10fdbe28592e492ef6903b82d2fc47bff930ea4
Reviewed-on: https://chromium-review.googlesource.com/1146729
Reviewed-by: Anders Ruud <andruud@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#577245}
[modify] https://crrev.com/4953b70f39f00c5be23b84aade0084c025cc709b/third_party/blink/renderer/core/css/style_engine_test.cc
[modify] https://crrev.com/4953b70f39f00c5be23b84aade0084c025cc709b/third_party/blink/renderer/core/dom/element.cc

ClusterFuzz has detected this issue as fixed in range 577244:577246.

Detailed report: https://clusterfuzz.com/testcase?key=6295165699096576

Fuzzer: ifratric-browserfuzzer-v3
Job Type: linux_ubsan_chrome
Platform Id: linux

Crash Type: Null-dereference READ
Crash Address: 0x000000000013
Crash State:
  blink::Node::MutableComputedStyle
  GetComputedStyle
  blink::Element::StyleForPseudoElement
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_chrome&range=565667:565668
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_chrome&range=577244:577246

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6295165699096576

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 6295165699096576 is verified as fixed, so closing issue as verified.

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