R1:dbcf41dbea00

Fix a couple more "URI->alter()" callsites in paging code

Summary: `grep` had a hard time finding these.

Test Plan: Will just hotfix this since I'm still reasonably in the deploy window, this currently fatals: <https://secure.phabricator.com/search/query/_dgatshiRBSy/#R>

Reviewers: amckinley

Differential Revision: https://secure.phabricator.com/D20186