use SkTaskGroup::batch

use SkTaskGroup::batch

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/67c71203a4e2e4f4be0a4e2293bec3a1bc1b07c8

[reed1, 2014-10-29 21:37:12]

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

[reed1, 2014-10-29 21:37:15]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2014-10-29 21:38:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688753002/1

[commit-bot: I haz the power, 2014-10-29 21:38:41]

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 2014-10-30 03:38 UTC

[mtklein, 2014-10-29 21:38:43]

lgtm

[commit-bot: I haz the power, 2014-10-29 21:41:50]

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

[commit-bot: I haz the power, 2014-10-29 21:41:52]

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...)

[mtklein, 2014-10-29 22:42:20]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-10-29 22:42:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688753002/1

[commit-bot: I haz the power, 2014-10-29 22:44:29]

Committed patchset #1 (id:1) as 67c71203a4e2e4f4be0a4e2293bec3a1bc1b07c8