Revert "surfaceflinger: Improve dithering method (2/2)"

This reverts commit f3165a68682a4c8fe7f1d5af8116e2d25dc75f72.
Revert "Revert "surfaceflinger: Improve dithering method (2/2)""

This reverts commit a51ae8230beee710460171ebdfb8aec6a767cff6.

I know compilation's gonna be... anyways :|