Fix git-try for people that use it over svn.
Fix git-try for people that use it over svn.

Original review url: http://codereview.chromium.org/225007 


git-svn-id: bd64dd6fa6f3f0ed0c0666d1018379882b742947@26928 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

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