The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f82d1989d2cd90127535ed6b667304474dbdc44f

commit f82d1989d2cd90127535ed6b667304474dbdc44f
Author: Biao She <bshe@chromium.org>
Date: Tue Nov 14 20:36:14 2017

Add opacity animation for speech_recognition UI and browser foreground group

Bug:  784437 
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I8cad580022b90debd4e59e43501a91cef036bcaa
Reviewed-on: https://chromium-review.googlesource.com/766570
Commit-Queue: Biao She <bshe@chromium.org>
Reviewed-by: Ian Vollick <vollick@chromium.org>
Reviewed-by: Yash Malik <ymalik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516412}
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/elements/transient_element.cc
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/elements/transient_element.h
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/elements/transient_element_unittest.cc
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/elements/ui_element.h
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/test/ui_scene_manager_test.cc
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/test/ui_scene_manager_test.h
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/ui_scene_constants.h
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/ui_scene_manager.cc
[modify] https://crrev.com/f82d1989d2cd90127535ed6b667304474dbdc44f/chrome/browser/vr/ui_scene_manager_unittest.cc