Treat 'revert' like 'update' in gclient.
Treat 'revert' like 'update' in gclient.

This cl ensures that gclient enforces sane revision overrides and
onfiguration when running a revert, just like it does on a normal sync/update.

R=iannucci@chromium.org
BUG=420919

Review URL: https://codereview.chromium.org/1160113003.

git-svn-id: bd64dd6fa6f3f0ed0c0666d1018379882b742947@295571 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

svn2github/chromium-depot-tools,svn2github/chromium-depot-tools,svn2github/chromium-depot-tools