Fix automate-git.py to pick up incremental changes in the remote CEF Git repository.

git-svn-id: http://chromiumembedded.googlecode.com/svn/trunk/cef3@1799 5089003a-bbd8-11dd-ad1f-f1f9622dbc98
Fix identification of SVN revision after picking up incremental changes in the remote CEF Git repository.

git-svn-id: http://chromiumembedded.googlecode.com/svn/trunk/cef3@1802 5089003a-bbd8-11dd-ad1f-f1f9622dbc98