Animates drawables in Notifications

Starts and stops drawables in BigPicture, Conversation, and
Messaging Template Notifications via the NotificationViewWrapper
by hooking into times when Icons should be animating.

Bug: 263414400
Test: Unit tests added to cover all files.
Change-Id: I91ba75ba881a88cadce47b3a76cf1b5eab29d5ec
14 files changed