This is needed in order to be able to commit when
working from a pure Git checkout, since the Git updater
is configured to sync using a http-URL
(in services/cron/git_updater/project_config.py)

Being able to use a pure Git checkout is a natural step
towards switching over libyuv to Git.

BUG=476598
TBR=fbarchard@google.com
TESTED=gclient config https://chromium.googlesource.com/external/libyuv --name=trunk
gclient sync
git auto-svn
# create local branch and edit
git cl upload
git cl dcommit

Review URL: https://webrtc-codereview.appspot.com/46119004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1383 16f28f9a-4ce2-e073-06de-1de4eb20be90