Fix crashes caused when SourceBuffer.remove() is called starting at the presentation duration.

media/filters/chunk_demuxer_unittest.cc

Index: media/filters/chunk_demuxer_unittest.cc
diff --git a/media/filters/chunk_demuxer_unittest.cc b/media/filters/chunk_demuxer_unittest.cc
index 67928e373afb7e2551613496d22343aa77317f52..6dd7192d4af8d69382c8cb1c83df9e93736f9fc3 100644
--- a/media/filters/chunk_demuxer_unittest.cc
+++ b/media/filters/chunk_demuxer_unittest.cc
@@ -3269,6 +3269,25 @@ TEST_P(ChunkDemuxerTest, Remove_AudioVideoText) {
   CheckExpectedBuffers(text_stream, "1 101 201");
 }
 
+TEST_P(ChunkDemuxerTest, Remove_StartAtDuration) {
+  ASSERT_TRUE(InitDemuxer(HAS_AUDIO));
+  DemuxerStream* audio_stream = demuxer_->GetStream(DemuxerStream::AUDIO);
+
+  AppendSingleStreamCluster(kSourceId, kAudioTrackNum,
+                            "0K 20K 40K 60K 80K 100K 120K 140K");
+
+  CheckExpectedRanges(kSourceId, "{ [0,160) }");
+  CheckExpectedBuffers(audio_stream, "0 20 40 60 80 100 120 140");
+
+  demuxer_->Remove(kSourceId,
+                   base::TimeDelta::FromSecondsD(demuxer_->GetDuration()),

[wolenetz, 2014/06/05 23:27:32]

demuxer_->GetDuration() will be much larger than 160ms. It's actually
kDefaultDuration() from InitDemuxer(), above. So I don't think this tests the
exact desired scenario of removal beginning at duration and buffered ends at
duration. Perhaps do a demuxer_->SetDuration(140) after InitDemuxer, add an
expectation of a call to SetDuration(160) prior to appending the cluster, and
confirm demuxer->GetDuration() is 160 prior to Remove()?

[acolwell GONE FROM CHROMIUM, 2014/06/06 00:40:07]

Done.

+                   kInfiniteDuration());
+
+  Seek(base::TimeDelta());
+  CheckExpectedRanges(kSourceId, "{ [0,160) }");
+  CheckExpectedBuffers(audio_stream, "0 20 40 60 80 100 120 140");
+}
+
 // Verifies that a Seek() will complete without text cues for
 // the seek point and will return cues after the seek position
 // when they are eventually appended.