Fix color space matrix hashing to avoid hashing the typemask

BUG=skia:

Change-Id: I8d4594fcf0eeebf598871bfe9203ed52460c98ce
Reviewed-on: https://skia-review.googlesource.com/6558
Reviewed-by: Mike Klein <mtklein@chromium.org>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
3 files changed