surfaceflinger: Consolidate display orientation compensation hooks

Dedupe rotation calculation code and make rotation a statically
available property in the DisplayDevice
Change-Id: Ic517ab0d2c05026cd6fa46d664aab7926be17b62
Merge "surfaceflinger: Consolidate display orientation compensation hooks" into android-4.4
Merge remote-tracking branch 'omni/android-4.4' into omni-4.4