Some distance field text optimizations.

Some distance field text optimizations.

- Add clipRect check
- Remove creation of scalerContext to check for color fonts in canDraw()
   (no longer needed)

BUG=skia:2933
Committed: https://skia.googlesource.com/skia/+/2faa2284357d7cec51b26d8251c53bc91251b1fe

[jvanverth1, 2014-10-31 18:55:06]

jvanverth@google.com changed reviewers:
+ egdaniel@google.com, robertphillips@google.com

[robertphillips, 2014-10-31 19:09:13]

lgtm

https://codereview.chromium.org/696503004/diff/1/src/gpu/GrDistanceFieldTextC...
File src/gpu/GrDistanceFieldTextContext.cpp (right):

https://codereview.chromium.org/696503004/diff/1/src/gpu/GrDistanceFieldTextC...
src/gpu/GrDistanceFieldTextContext.cpp:484: const SkMatrix& ctm =
fContext->getMatrix();
Is there anything we can do with the device space rect?

[jvanverth1, 2014-10-31 19:21:12]

The CQ bit was checked by jvanverth@google.com

[commit-bot: I haz the power, 2014-10-31 19:22:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/696503004/1

[commit-bot: I haz the power, 2014-10-31 19:40:19]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-10-31 19:40:20]

Try jobs failed on following builders:
  Build-Win-VS2013-x86-Debug-Trybot on client.skia.compile
(http://build.chromium.org/p/client.skia.compile/builders/Build-Win-VS2013-x86...)

[jvanverth1, 2014-10-31 19:51:52]

The CQ bit was checked by jvanverth@google.com

[commit-bot: I haz the power, 2014-10-31 19:52:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/696503004/20001

[commit-bot: I haz the power, 2014-10-31 19:52:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/696503004/20001

[commit-bot: I haz the power, 2014-10-31 20:00:00]

Committed patchset #2 (id:20001) as 2faa2284357d7cec51b26d8251c53bc91251b1fe