Switch polling URL to git-on-borg.
Switch polling URL to git-on-borg.

TBR=mmoss@chromium.org,cmp@chromium.org
Review URL: https://codereview.chromium.org/12152002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@179999 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build