refactor SkBitmapProcState_opts.h a bit

Shouldn't be any major change in here, and the only codegen change
should be the easy-to-predict branch on alpha < 256.  This is mostly
about makings sure I understand and can read the code.

Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I3e6260be76595275ba177551cbb8f4a84e4970ec
Reviewed-on: https://skia-review.googlesource.com/c/171585
Auto-Submit: Mike Klein <mtklein@google.com>
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Herb Derby <herb@google.com>
1 file changed