Null check color_space_ptr in draw functor v2

Missed toXYZD50 usage last time. Still assume sRGB if null.

Bug: 187798471
Test: Manually tested setting color_space_ptr to null in
      GL/VKFunctorDrawable
Change-Id: Idee2660d368dd55e45f5d07d52839105ba951ff3
1 file changed