Remove unnecessary references to URLRequestContext.

Remove unnecessary references to URLRequestContext.

The actual URLRequestContext used by the Chromium embedder here is the "proxy
script fetcher" URLRequestContext. It is owned by the browser process's
IOThread. Therefore, there's no need to refcount it within objects owned by 
the ProxyService of that URLRequestContext.

BUG=58859
TEST=none


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=131562

[eroman, 2012-04-09 22:41:05]

LGTM.

cc-ing @joi as FYI

[commit-bot: I haz the power, 2012-04-10 06:20:25]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/willchan@chromium.org/10024019/1

[commit-bot: I haz the power, 2012-04-10 06:52:48]

Try job failure for 10024019-1 on android for step "update".
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=android&nu...

Step "update" is always a major failure.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-04-10 08:55:21]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/willchan@chromium.org/10024019/1

[Jói, 2012-04-10 08:57:08]

LGTM, thanks Will.

[commit-bot: I haz the power, 2012-04-10 08:58:41]

Try job failure for 10024019-1 on win for step "update".
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win&number...

Step "update" is always a major failure.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-04-10 15:09:21]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/willchan@chromium.org/10024019/1

[commit-bot: I haz the power, 2012-04-10 16:57:12]

Change committed as 131562