separate out the scaline-choosing to simplify chooseProcs

separate out the scaline-choosing to simplify chooseProcs

BUG=skia:
TBR=

Committed: https://skia.googlesource.com/skia/+/26feeba2678e82ada6ee0c5096a95a8ef2a00c60

[reed1, 2015-01-14 19:00:36]

reed@google.com changed reviewers:
+ robertphillips@google.com

[reed1, 2015-01-14 19:00:39]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2015-01-14 19:00:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/796063007/1

[commit-bot: I haz the power, 2015-01-14 19:00:56]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2015-01-15 01:00 UTC

[reed1, 2015-01-14 20:28:09]

The CQ bit was unchecked by reed@google.com

[reed1, 2015-01-14 20:28:13]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2015-01-14 20:28:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/796063007/1

[commit-bot: I haz the power, 2015-01-14 20:28:26]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/26feeba2678e82ada6ee0c5096a95a8ef2a00c60

[robertphillips, 2015-01-14 21:54:21]

lgtm + a dox/naming suggestion

https://codereview.chromium.org/796063007/diff/1/src/core/SkBitmapProcState.h
File src/core/SkBitmapProcState.h (right):

https://codereview.chromium.org/796063007/diff/1/src/core/SkBitmapProcState.h...
src/core/SkBitmapProcState.h:137: bool chooseProcs(const SkMatrix& inv, const
SkPaint&);
clampClamp -> clampInBothDirs ?