Add kRGBX_8888, kRGBA_1010102, and kRGBX_1010102 color types. Unused for now.

BUG= skia:7533

Change-Id: I4b3f6b827fd833ba2d07895884d2abc9a3132366
Reviewed-on: https://skia-review.googlesource.com/99781
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Brian Salomon <bsalomon@google.com>
9 files changed