CC Animation: Rename HasAnimation to HasAnimationForTesting.

Also, erase Layer::IsActive method (it is meaningless and not used anywhere)

BUG=575041
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1797703002

Cr-Commit-Position: refs/heads/master@{#380926}
9 files changed