The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1d35eeb7d806d06efee7bea16cc78e174e1d0c82

commit 1d35eeb7d806d06efee7bea16cc78e174e1d0c82
Author: wutao <wutao@chromium.org>
Date: Thu Oct 12 23:01:24 2017

Modify Trilinear Filtering API in ui::Layer.

This is a preparation work to use the trilinear filtering in various ui
effects, such as overview and window switcher. By adding a request
counter can allow multiple requests applied to the same layer and make
it possible to set and restore the layer trilinear filtering status to
the previous status by using ScopedLayerAnimationSettings.

Bug:  774224 
Test: Added layer_unittests
Change-Id: I6b2e130ae62a4af619459f9132ee82c34a19083e
Reviewed-on: https://chromium-review.googlesource.com/717145
Reviewed-by: David Reveman <reveman@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Tao Wu <wutao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508520}
[modify] https://crrev.com/1d35eeb7d806d06efee7bea16cc78e174e1d0c82/ui/compositor/layer.cc
[modify] https://crrev.com/1d35eeb7d806d06efee7bea16cc78e174e1d0c82/ui/compositor/layer.h
[modify] https://crrev.com/1d35eeb7d806d06efee7bea16cc78e174e1d0c82/ui/compositor/layer_unittest.cc