Revert "SF: Block gpu rendering for virtual display widevine level3"

This reverts commit 149007998be338900cc2c56a4c81f865b1db6f2e.
Revert "SurfaceFlinger: Change to support framebuffer flip for 2D blitters"

This reverts commit 4f089f8886cf1d9ef5e88a8d471d8785adf6365e.

Conflicts:

	services/surfaceflinger/DisplayHardware/HWComposer.cpp