Fix memory leak with RenderNodeAnimator

Update View logic to cancel all RenderNodeAnimators
when it is detached from a window.
Updated HWUI Animation logic to enable a cancellation
flag to cancel all animators operating on a RenderNode
whenever the staging parameters are pushed to RenderThread

Fixes: 229136453
Test: Added core test to RenderNodeAnimatorTests
Change-Id: Id674e8474757bfc8dfe30394dde29da49d139bfc
6 files changed