Setting this will make the harness block in the chain-function, and
then release when gstcheck.harness.Harness.pull or gstcheck.harness.Harness.tryPull is called.
Can be useful when wanting to control a src-element that is not implementing
gst.clock.Clock.idWait so it can't be controlled by the #GstTestClock, since
it otherwise would produce buffers as fast as possible.
Setting this will make the harness block in the chain-function, and then release when gstcheck.harness.Harness.pull or gstcheck.harness.Harness.tryPull is called. Can be useful when wanting to control a src-element that is not implementing gst.clock.Clock.idWait so it can't be controlled by the #GstTestClock, since it otherwise would produce buffers as fast as possible.
MT safe.