avformat/mov: Check if DTS is AV_NOPTS_VALUE in mov_find_next_sample().

Signed-off-by: Dale Curtis <dalecurtis@chromium.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit bf446711bc)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/mov.c

@@ -7019,7 +7019,7 @@ static AVIndexEntry *mov_find_next_sample(AVFormatContext *s, AVStream **st)
             av_log(s, AV_LOG_TRACE, "stream %d, sample %d, dts %"PRId64"\n", i, msc->current_sample, dts);
             if (!sample || (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL) && current_sample->pos < sample->pos) ||
                 ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) &&
-                 ((msc->pb != s->pb && dts < best_dts) || (msc->pb == s->pb &&
+                 ((msc->pb != s->pb && dts < best_dts) || (msc->pb == s->pb && dts != AV_NOPTS_VALUE &&
                  ((FFABS(best_dts - dts) <= AV_TIME_BASE && current_sample->pos < sample->pos) ||
                   (FFABS(best_dts - dts) > AV_TIME_BASE && dts < best_dts)))))) {
                 sample = current_sample;