Implement R5G6B5 write masking.

Bug 20891368

Change-Id: Ie4e153330c0a422c849953caf02b199df860b8f0
Reviewed-on: https://swiftshader-review.googlesource.com/3256
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
3 files changed