WindowState: Introduce applyWithNextDraw, port Seamless Rotation

While BLASTSyncEngine is a good primitive for syncing changes to
multiple window containers, it's complexity introduces constraints,
namely that only one BLASTSyncEngine sync may be active at a time (for
a given window container). As more and more parts of the WM wish to rely
on BLASTSync, this can create a difficult coordination problem. In this
CL we expose a per WindowState sync mechanism (applyWithNextDraw) which
can compose with BLASTSyncEngine transactions, and can be used by
multiple features simultaneously on a given WindowState.

This system works by maintaining a list of "DrawHandlers"
(Consumer<Transaction>), in each WindowState. At a high level, when
adding a draw handler we request the client to redraw, and when
we receive the Transaction containing the frame in finishDrawing
we invoke the handler, giving it a chance to append to the transaction
before it is applied or merged in to a higher level BLASTSyncEngine
transaction.

Next we port seamless rotation to this system. The concept is relatively
easy, the setup proceeds as before: In the same transaction we rotate
the display projection we create a SeamlessRotator to unrotate the apps
original orientation buffer. Seamless rotation requires us to remove
this transform when the app redraws, and this is trivially accomplished
with the applyWithNextDraw primitive.

Bug: 168505645
Bug: 181424834
Test: Existing tests pass
Change-Id: Ie84d99e58b8d0efedbedab0ea48a441826e3a7bf

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