WindowContainerTransaction: Provide non-BLAST bounds change sync

This is to enable landing the SysUI driven PiP animation without BLAST. Without
BLAST we can't support multi container sync, multi buffer sync, etc, but we can
support the same sort of synchronization we've supported before. Let's recall how
the old PIP animation works: At the end of the enter animation, or the beginning
of the leave animation, the Surface changes size (When the Windowing mode changes).
We detect this size change deep in the guts of WindowStateAnimator, and when
we detect that we are called from "relayoutWindow" defer a transaction changing
the PIP scaling factors. This approach is we simply allow SysUI to set a pending
Transaction on a task via the WindowContainerTransaction API. The next BASE_APPLICATION
window to resize in this task will consume this transaciton, and defer the transaction
until the frame in which it resizes.

Bug: 139371701
Bug: 139371701
Test: Manual test with pending SysUI branch
Change-Id: I1e757d87e2f276db626de00685b0432508ac6d62