GitLab

From a performance standpoint, it is important that windows that are
off-screen don't animate.

R=sammiequon@chromium.org

Test: manual
Bug: 981190

Change-Id: I4ba972c237e51425a4650a3aaba839ddfe2c2df0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733718
Commit-Queue: Danton Vu <dantonvu@google.com>
Reviewed-by: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#684148}