Problem : Text samples have variable length and therefore act
more like continuous samples whereas audio and video
act more like discrete samples. Since we use sample
start time, a cue event could be inserted after the
start time of the last text sample and never get
inserted as there are no more samples.
Change : After all streams have requested flushing, we make sure
to collect all remaining cue events from the sync point
queue and insert them into each stream.
Issue #362
Change-Id: Id8f136f7ef53531f7a7f412613eac352324e0130
Create an end-to-end test for ad cues. This test's final result is not
correct but illustrates the problem we have in the cue insertion and will
be fixed by a later CL.
Change-Id: Ia8b43a53848941be52cf9ade018668e6477e8df2