Remove webkitpy.thirdparty.mock, webkitpy.common.webkitunittest.

Remove webkitpy.thirdparty.mock, webkitpy.common.webkitunittest.

More webkitpy cleanup.

webkitunittest isn't needed once we required Python 2.7.

mock.Mock() was really only being used in one file (and didn't need to be used
there, either), and I'm not generally fan of the generic Mock approach
it uses (preferring concrete mock objects or fakes).

R=abarth@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=180404

[Dirk Pranke, 2014-08-16 01:01:05]

ping?

[abarth-chromium, 2014-08-16 01:24:25]

lgtm

[Dirk Pranke, 2014-08-16 01:26:11]

On 2014/08/16 01:24:25, abarth wrote:
> lgtm

thanks!

[Dirk Pranke, 2014-08-16 01:26:14]

The CQ bit was checked by dpranke@chromium.org

[commit-bot: I haz the power, 2014-08-16 01:26:44]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dpranke@chromium.org/467133003/1

[commit-bot: I haz the power, 2014-08-16 03:05:35]

Committed patchset #1 (1) as 180404