Move c/r/extensions/* into extensions namespace

Move c/r/extensions/* into extensions namespace

Moved all classes and files in c/r/extensions into the extensions namespace.

BUG=140056, 117261
TBR=jam@chromium.org


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=150402

[Devlin, 2012-08-01 20:22:54]

Refactor; please review when you get a chance.  (Sorry for the large number of
files.)

[miket_OOO, 2012-08-03 16:41:54]

I knew this day would come! Thank you for doing this.

For changed files, I reviewed that there were only namespace changes. For moved
files, I did a cursory review of the new files and didn't see anything but
namespace changes, but I did not do a line-for-line comparison between deleted
and added files. If an evil person took over your account and inserted malicious
code in the new files, the plan is likely to succeed.

LGTM. And again, thanks!

[commit-bot: I haz the power, 2012-08-07 18:37:56]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rdevlin.cronin@chromium.org/10821133/8001

[commit-bot: I haz the power, 2012-08-07 21:08:46]

Change committed as 150402

[not at google - send to devlin, 2012-08-08 07:33:47]

I think this change is going to make it hard to cherry pick anything that
touches chrome/extensions/renderer into the m22 branch...