Fix muxed MP4 parsing so it won't crash on partial media segment appends.

media/formats/mp4/mp4_stream_parser_unittest.cc

Index: media/formats/mp4/mp4_stream_parser_unittest.cc
diff --git a/media/formats/mp4/mp4_stream_parser_unittest.cc b/media/formats/mp4/mp4_stream_parser_unittest.cc
index ef0bd44b3a548e5da5bf16c99b92f19a0f20d812..8805c05c3a75d6e7a4f55bfd7ba6f4dc1fbcfec3 100644
--- a/media/formats/mp4/mp4_stream_parser_unittest.cc
+++ b/media/formats/mp4/mp4_stream_parser_unittest.cc
@@ -31,7 +31,8 @@ static const char kMp4InitDataType[] = "video/mp4";
 class MP4StreamParserTest : public testing::Test {
  public:
   MP4StreamParserTest()
-      : configs_received_(false) {
+      : configs_received_(false),
+        lower_bound_(base::TimeDelta::Max()) {
     std::set<int> audio_object_types;
     audio_object_types.insert(kISO_14496_3);
     parser_.reset(new MP4StreamParser(audio_object_types, false));
@@ -40,6 +41,7 @@ class MP4StreamParserTest : public testing::Test {
  protected:
   scoped_ptr<MP4StreamParser> parser_;
   bool configs_received_;
+  base::TimeDelta lower_bound_;
 
   bool AppendData(const uint8* data, size_t length) {
     return parser_->Parse(data, length);
@@ -73,7 +75,6 @@ class MP4StreamParserTest : public testing::Test {
     return true;
   }
 
-
   void DumpBuffers(const std::string& label,
                    const StreamParser::BufferQueue& buffers) {
     DVLOG(2) << "DumpBuffers: " << label << " size " << buffers.size();
@@ -96,6 +97,24 @@ class MP4StreamParserTest : public testing::Test {
     if (!text_map.empty())
       return false;
 
+    // Find the second highest timestamp so that we know what the
+    // timestamps on the next set of buffers must be >= than.
+    base::TimeDelta audio = !audio_buffers.empty() ?
+        audio_buffers.back()->GetDecodeTimestamp() : kNoTimestamp();
+    base::TimeDelta video = !video_buffers.empty() ?
+        video_buffers.back()->GetDecodeTimestamp() : kNoTimestamp();
+    base::TimeDelta second_highest_timestamp =
+        (audio == kNoTimestamp() ||
+         (video != kNoTimestamp() && audio > video)) ? video : audio;
+
+    DCHECK(second_highest_timestamp != kNoTimestamp());
+
+    if (lower_bound_ != kNoTimestamp() &&
+        second_highest_timestamp < lower_bound_) {
+      return false;
+    }
+
+    lower_bound_ = second_highest_timestamp;
     return true;
   }
 
@@ -108,10 +127,12 @@ class MP4StreamParserTest : public testing::Test {
 
   void NewSegmentF() {
     DVLOG(1) << "NewSegmentF";
+    lower_bound_ = kNoTimestamp();
   }
 
   void EndOfSegmentF() {
     DVLOG(1) << "EndOfSegmentF()";
+    lower_bound_ = base::TimeDelta::Max();
   }
 
   void InitializeParser() {