Support wide color in GrLatticeOp

Like other image drawing, paint color is only used when drawing alpha
images, so I had to add a new GM to trigger the relevant code path.
That GM previously drew wrong (clipped color) in glenarrow, and now
draws correctly (matching enarrow).

Bug: skia:
Change-Id: I12c19c2afba29d5176b3ac60ef840d849107bb17
Reviewed-on: https://skia-review.googlesource.com/c/179987
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
2 files changed