frameworks/native: surfaceflinger: Add Group cache

SF currently provides feature for color change
for users with color vision impairement.
This feature, creates fbos every frame with
a new texture of viewport size causing performance
degradation. Add Group cache so that, FBO/Textures
are cached.

Change-Id: I54a3d52f790a98ce730601d2003ad6ae9456b992
CRs-fixed: 669485