tree b4192fb799dab5327c6559f3aff5f19a1a268967
parent 3f55eed73f5af405909c2c10bff179d80526d423
author reed <reed@chromium.org> 1428003984 -0700
committer Commit bot <commit-bot@chromium.org> 1428003984 -0700

experimental speedup some xfermodes with Sk4f

Old:
   7M	1	11.1ms	11.3ms	11.3ms	11.6ms	1%	▅▄▂▂▁▁▄▄█▇	8888	Xfermode_Screen
   7M	1	10.7ms	10.9ms	10.9ms	11.1ms	1%	▄▄▄▇▃▁█▄▂▅	8888	Xfermode_Modulate
   7M	1	7.86ms	8.03ms	8ms	8.18ms	1%	█▇▅▁▃▃▂▃▆▅	8888	Xfermode_Plus
   7M	1	14.6ms	14.8ms	14.8ms	15.1ms	1%	▄█▆▅▄▁▁▆▄▆	8888	Xfermode_Xor
   7M	1	13ms	13.5ms	13.4ms	13.8ms	2%	▅▃▇▁█▂▃▅▃▅	8888	Xfermode_DstATop
   7M	1	13.1ms	13.4ms	13.3ms	13.6ms	1%	▄▁▁▆▅▄▇▆█▂	8888	Xfermode_SrcATop

New:
   7M	1	6.99ms	7.19ms	7.4ms	8.98ms	8%	▁▂▁▃▂█▁▂▂▂	8888	Xfermode_Screen
   7M	1	5.27ms	5.46ms	5.46ms	5.89ms	3%	▁▁▅▁▂█▄▃▄▃	8888	Xfermode_Modulate
   7M	1	6.8ms	7.04ms	7.27ms	8.53ms	8%	▂▁█▁▁▂▂▂▂▇	8888	Xfermode_Plus
   7M	1	9ms	9.2ms	9.33ms	10.5ms	5%	▁█▃▁▂▁▁▁▅▂	8888	Xfermode_Xor
   7M	1	8.34ms	8.57ms	8.73ms	10.6ms	8%	▁▁▁▂▂▂▂▂▂█	8888	Xfermode_DstATop
   7M	1	8.38ms	8.62ms	8.91ms	10.3ms	8%	▁▃▁▂▇▂▁▂▁█	8888	Xfermode_SrcATop

Need to define SK_SUPPORT_LEGACY_SCALAR_XFERMODES in chrome to suppress change (see https://codereview.chromium.org/1054083002/)

Review URL: https://codereview.chromium.org/1043413002