Revert of Gerrit git cl: temporary disable cc option on upload. (patchset #1 id:1 of https://codereview.chromium.org/1895863002/ )

Reason for revert:
We've whitelisted cc-ed emails in Gerrit, and so let's try setting cc= again.

Original issue's description:
> Gerrit git cl: temporary disable cc option on upload.
> 
> Gerrit doesn't allow arbitrary non-member emails for now,
> thus removign this feature until either Gerrit allows it,
> or we have a per-repo opt-in way.
> 
> TBR=andybons@chromium.org
> BUG=604377
> 
> Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=299988

TBR=andybons@chromium.org,sergiyb@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=604377

Review-Url: https://codereview.chromium.org/2034143002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300694 0039d316-1c4b-4281-b951-d872f2087c98