Return a list of (time, (trip, index), is_timepoint).

    time: an integer. It might be interpolated.
    trip: a Trip object.
    index: the offset of this stop in trip.GetStopTimes(), which may be
      different from the stop_sequence.
    is_timepoint: a bool

def GetStopTimeTrips(self, schedule=None):
    """Return a list of (time, (trip, index), is_timepoint).

    time: an integer. It might be interpolated.
    trip: a Trip object.
    index: the offset of this stop in trip.GetStopTimes(), which may be
      different from the stop_sequence.
    is_timepoint: a bool
    """
    time_trips = []
    for trip, index in self._GetTripIndex(schedule):
      secs, stoptime, is_timepoint = trip.GetTimeInterpolatedStops()[index]
      time_trips.append((secs, (trip, index), is_timepoint))
    return time_trips