pay some attention to apply_tf()

Our sign-handling code here is very first-draft.

This new version does the same thing with much cheaper instructions.
Should be a small, free performance win.

Change-Id: I858ae734b57a0595fbf3f72c97bbe5a5a6d3d6b6
Reviewed-on: https://skia-review.googlesource.com/144624
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
1 file changed