Remove PreferenceAPI dependency from ExtensionPrefs.

Remove PreferenceAPI dependency from ExtensionPrefs.

The only dependency here is on some static methods that
are only used by ExtensionPrefs. These should live inside
the ExtensionPrefs module.

(clang_format also applied, pardon the dust)

BUG=357634, 162530
R=scheib@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=260272

[scheib, 2014-03-28 16:52:25]

lgtm

[scheib, 2014-03-28 16:52:25]

lgtm

lgtm

[Ken Rockot(use gerrit already), 2014-03-28 16:54:54]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-03-28 16:57:07]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rockot@chromium.org/217053003/20001

[commit-bot: I haz the power, 2014-03-28 17:31:59]

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

[commit-bot: I haz the power, 2014-03-28 17:31:59]

Retried try job too often on chromium_presubmit for step(s) presubmit
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=chromium_p...

[Ken Rockot(use gerrit already), 2014-03-28 17:34:15]

Oops, James can you please stamp for DEPS?

[James Cook, 2014-03-28 17:43:04]

DEPS lgtm

[Ken Rockot(use gerrit already), 2014-03-28 17:43:45]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-03-28 17:47:11]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rockot@chromium.org/217053003/20001

[commit-bot: I haz the power, 2014-03-28 21:00:16]

Change committed as 260272