This allows datatype SyncableServices to request a fresh copy of the data
that was previously only passed over in batch form during
MergeDataAndStartSyncing. Since it can be slow, it should be used
sparingly.
Though currently unused, Sessions will soon need this behavior to deal with
cases where (e.g) the local session is deleted by a foreign client, thereby
corrupting TabNodePool tracking and requiring a full re-association.
TBR=zea@chromium.org
^Many function signature touchups under browser/
BUG=98892
Review URL: https://codereview.chromium.org/23129007
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221540 0039d316-1c4b-4281-b951-d872f2087c98
fe4b4ca1cb