Fix exception with "phabricator.allowed-uris" when trying to set cookies

Summary: The `phabricator.allowed-uris` config setting is not checked properly when trying to set cookies.

Test Plan:
Set an alternate URI, then accessed Phabricator. No longer received a secondary cookie error.

Hit the new exceptions to test them:

{F51131}
{F51132}

Reviewers: btrahan, garoevans

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D6528