to
LAST_SAMPLE_DURATION_BEHAVIOR_SET_FROM_END_OF_STREAM_BUFFER_OR_DUPLICATE_PREVIOUS
This CL also combines LAST_SAMPLE_DURATION_BEHAVIOR_SET_FROM_END_OF_STREAM_BUFFER
and LAST_SAMPLE_DURATION_BEHAVIOR_DUPLICATE_PREVIOUS.
The reason for combining the two enums is that, when the option
to use END_OF_STREAM_BUFFER is selected and if the EOS buffer is
not provided then the muxer anyways fallbacks to duplicate
duration behavior.
The last sample with 0 durations seems less useful so
change the default behavior to non-zero duration.
This will also match the behavior with MediaMuxer.
PiperOrigin-RevId: 675189932