command_buffer: Implement CHROMIUM_framebuffer_mixed_samples extension
Implement a pseudo-extension that allows using attachments of different
sample counts in framebuffers.
The extension is implemented by the means of
GL_NV_framebuffer_mixed_samples.
At the present form, should be usable in Skia to implement mixed
samples.
BUG=506765
TBR=jam@chromium.org
Review URL: https://codereview.chromium.org/1218223005
Cr-Commit-Position: refs/heads/master@{#366403}
CrOS-Libchrome-Original-Commit: a9d27e7cf8e6e08c5cbf56b3f600d02e150313be
3 files changed