Allow Core Animation compositor to use some scaled filter effects.

Filter scaling has no effect on filter effects that are not BLUR or DROP_SHADOW.

BUG=581526
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Review-Url: https://codereview.chromium.org/2188523006
Cr-Commit-Position: refs/heads/master@{#408286}
5 files changed