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/+/dc8d14d9a16b28d12b8380d0a5490fe4a747a65a (Enable mojo input messages on all platforms other than Android webview.).

If this is incorrect, please remove the owner and apply the Test-Predator-Wrong-CLs label.

ClusterFuzz has detected this issue as fixed in range 519404:519436.

Detailed report: https://clusterfuzz.com/testcase?key=5093946152976384

Fuzzer: inferno_twister
Job Type: linux_ubsan_vptr_content_shell_drt
Platform Id: linux

Crash Type: Null-dereference READ
Crash Address: 0x000000000008
Crash State:
  content::WidgetInputHandlerManager::GetWidgetInputHandlerHost
  content::RenderWidget::OnDidOverscroll
  content::RenderWidgetInputHandler::DidOverscrollFromBlink
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=519312:519325
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_content_shell_drt&range=519404:519436

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5093946152976384

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 5093946152976384 is verified as fixed, so closing issue as verified.

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

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/84c0905079cba6b4977956949c6d22ac57c85761

commit 84c0905079cba6b4977956949c6d22ac57c85761
Author: Dave Tapuska <dtapuska@chromium.org>
Date: Tue Nov 28 18:10:05 2017

Fix nullptr access with MojoInputMessages on.

With event sender input is possibly injected solely on the main thread and
a host may not be bound yet. So protect against null host objects on
the main thread.

BUG= 788886 

Change-Id: I6b8d1449ce01e3a1f0872133440839fa445d1567
Reviewed-on: https://chromium-review.googlesource.com/793971
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#519746}
[modify] https://crrev.com/84c0905079cba6b4977956949c6d22ac57c85761/content/renderer/input/widget_input_handler_manager.cc
[modify] https://crrev.com/84c0905079cba6b4977956949c6d22ac57c85761/content/renderer/render_widget.cc