The code was polling the input chunk duration after emptying out the
chunk's samples, which resulted in an input duration account sitting at
exactly zero, so the end overrun flush would not be cut short properly,
resulting in gaps between tracks.
Correct the input sum to tabulate before emptying the input chunk, so
output remains properly gapless.
Signed-off-by: Christopher Snowhill <kode54@gmail.com>
f251c91f02