Handle content insets for snapshots

Pass information about content insets of a snapshotted task to
SystemUI and use it there to correctly offset the snapshot
when drawing.

Test: Open app, go to recents, make sure app aligns before
and after the animation.
Bug: 31339431
Change-Id: I2ff9bd44534bd8f66b591385da1e1e3aec40b6c5
21 files changed