The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fb6613a035e615799d30f141cc4d140dc06d134f

commit fb6613a035e615799d30f141cc4d140dc06d134f
Author: wutao <wutao@chromium.org>
Date: Thu Sep 07 21:43:36 2017

CrOS: Cache render surface in hide animation.

Cache render surface in animation can improve the UI performance
significantly. We have built up fundamental blocks already. In this
cl, we are caching the render surface in hide animation.

Performance improvement:
Linux build: ~30%
KEVIN: ~15%

Bug:  756693 ,  753224 
Test: Tested improvement with/out cache.
Change-Id: I539a8407ae9742593a4a44de8f2542fb5f2630f9
Reviewed-on: https://chromium-review.googlesource.com/620132
Commit-Queue: Tao Wu <wutao@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: David Reveman <reveman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#500398}
[modify] https://crrev.com/fb6613a035e615799d30f141cc4d140dc06d134f/ui/wm/core/window_animations.cc