SF: DisplayCommand.colorTransform is just a matrix

Remove the hint from DisplayCommand.colorTransform as currently
we only use ColorTransform::IDENTITY and ColorTransform::ARBITRARY_MATRIX,
which both can be expressed using a matrix.

Bug: 208879711
Test: VTS
Change-Id: I1c335647aabb7f89c2c89e54abfc839d10a659fb
11 files changed