Changes Dawn and Tint to use a 3x3 matrix for external texture
YUV-to-RGB conversions. This will allow us to use standard matrices
as they exist in SkYuvMath.
Bugs: dawn::1082
Change-Id: I8e0c7c3dc1c085d8f336da956aea9496913b70fa
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/86847
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Brandon1 Jones <brandon1.jones@intel.com>