Fix the author search for branches (only an issue on reverts), looking at trunk w/ the revision won't tell you
the correct author.
Review URL: http://codereview.chromium.org/505053

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@35009 0039d316-1c4b-4281-b951-d872f2087c98