Adjusts the rate and time of clock. A rate of 1/1 is the normal speed of the clock. Values bigger than 1/1 make the clock go faster.

internal and external are calibration parameters that arrange that Clock.getTime should have been external at internal time internal. This internal time should not be in the future; that is, it should be less than the value of Clock.getInternalTime when this function is called.

Subsequent calls to Clock.getTime will return clock times computed as follows:

|[ time = (internal_time - internal) * rate_num / rate_denom + external

This formula is implemented in [gstreamer.Clock.Clock.adjustUnlocked|Clock.adjustUnlocked]. Of course, it
tries to do the integer arithmetic as precisely as possible.

Note that [gstreamer.Clock.Clock.getTime|Clock.getTime] always returns increasing values so when you
move the clock backwards, [gstreamer.Clock.Clock.getTime|Clock.getTime] will report the previous value
until the clock catches up.

MT safe.

    internal = a reference internal time
    external = a reference external time
    rateNum = the numerator of the rate of the clock relative to its
        internal time
    rateDenom = the denominator of the rate of the clock