Extract application window usage of SurfaceController.

Abstract the usage of SurfaceController from wm w.r.t
application windows in to a new WindowSurfaceController
class. This class tracks boring book keeping, logging,
errors, etc...to lend clarity to difficult policy
code in WindowStateAnimator et al.

Change-Id: Ifcd5d48a51e68564f49e799ae793b320cac88645