Modify string to reflect that supervised user syncing is now possible.

BUG=313220
NOTRY=TRUE

Review URL: https://codereview.chromium.org/163673002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251055 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251055
Docserver: Add clean URL support to the GCS content providers.

BUG=294008
TBR=yoz@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/163813002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251056 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251056