Merge "Only generate paint/mask bitmap when starting animations" into sc-dev...

Merge "Only generate paint/mask bitmap when starting animations" into sc-dev am: 7df767f3 am: e0ad3c6f am: 2858098d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14390053

Change-Id: I6964e9156c30dad57cdb3ad69a5223c5602e7833