'Add a count to the amount this thread has transferred.
Each time a thread transfers some data, it should call this method to
note the amount sent. The counts may be rotated if sufficient time
has passed since the last rotation.
Args:
throttle_name: The name of the throttle to add to.
token_count: The number to add to the throttle counter.'

def AddTransfer(self, throttle_name, token_count):

    self.VerifyThrottleName(throttle_name)
    transferred = self.transferred[throttle_name]
    try:
        transferred[id(threading.currentThread())] += token_count
    except KeyError:
        thread = threading.currentThread()
        raise ThreadNotRegisteredError(('Unregistered    thread    accessing    throttled    datastore    stub:    id    =    %s\nname    =    %s' % (id(thread), thread.getName())))
    if ((self.last_rotate[throttle_name] + self.ROTATE_PERIOD) < self.get_time()):
        self._RotateCounts(throttle_name)
