Maybe add CORS headers to data reduction proxy redirect

Maybe add CORS headers to data reduction proxy redirect

When the data reduction proxy responds with a bypass message,
chromium constructs a redirect response and feeds that through
the network stack. This results in the request being retried
directly to the origin. If the original request had an
Origin header, then the manufactured redirect should have the
appropriate CORS headers.

BUG=415644
Committed: https://crrev.com/e2c9516537409ac095d0def19c51710def704926
Cr-Commit-Position: refs/heads/master@{#296942}

[bengr, 2014-09-25 23:04:53]

Patchset #1 (id:1) has been deleted

[bengr, 2014-09-25 23:05:07]

bengr@chromium.org changed reviewers:
+ marq@chromium.org

[marq (ping after 24h), 2014-09-26 07:58:02]

lgtm

[bengr, 2014-09-26 14:12:42]

The CQ bit was checked by bengr@chromium.org

[commit-bot: I haz the power, 2014-09-26 14:13:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/603323002/20001

[commit-bot: I haz the power, 2014-09-26 15:20:42]

Committed patchset #1 (id:20001) as dc6809b7ca7ee59b9da7e4f9be9786e2b322935f

[commit-bot: I haz the power, 2014-09-26 15:21:28]

Patchset 1 (id:??) landed as
https://crrev.com/e2c9516537409ac095d0def19c51710def704926
Cr-Commit-Position: refs/heads/master@{#296942}