Return an error on Multiple AUs in a PES.

HLS spec recommends a single access unit(AU) in a packetized elementary stream(PES) so that each access unit can
be assigned a unique PTS and DTS. The change makes es_parser_h264 return an error if the AU cannot be assigned a PTS and DTS.

BUG=254214

Review URL: https://codereview.chromium.org/136703005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245347 0039d316-1c4b-4281-b951-d872f2087c98

media/mp2t/es_parser_h264.cc

@@ -216,7 +216,7 @@ bool EsParserH264::ParseInternal() {
 
     // Emit a frame if needed.
     if (nal_unit_type == kNalUnitTypeAUD)
-      EmitFrameIfNeeded(es_pos_);
+      RCHECK(EmitFrameIfNeeded(es_pos_));
 
     // Skip the syncword.
     es_pos_ += syncword_length;
@@ -225,21 +225,24 @@ bool EsParserH264::ParseInternal() {
   return true;
 }
 
-void EsParserH264::EmitFrameIfNeeded(int next_aud_pos) {
+bool EsParserH264::EmitFrameIfNeeded(int next_aud_pos) {
   // There is no current frame: start a new frame.
   if (current_access_unit_pos_ < 0) {
     StartFrame(next_aud_pos);
-    return;
+    return true;
   }
 
   // Get the access unit timing info.
-  TimingDesc current_timing_desc;
+  TimingDesc current_timing_desc = {kNoTimestamp(), kNoTimestamp()};
   while (!timing_desc_list_.empty() &&
          timing_desc_list_.front().first <= current_access_unit_pos_) {
     current_timing_desc = timing_desc_list_.front().second;
     timing_desc_list_.pop_front();
   }
 
+  if (current_timing_desc.pts == kNoTimestamp())
+    return false;
+
   // Emit a frame.
   int raw_es_size;
   const uint8* raw_es;
@@ -256,6 +259,7 @@ void EsParserH264::EmitFrameIfNeeded(int next_aud_pos) {
 
   // Set the current frame position to the next AUD position.
   StartFrame(next_aud_pos);
+  return true;
 }
 
 void EsParserH264::StartFrame(int aud_pos) {

media/mp2t/es_parser_h264.h

@@ -55,7 +55,8 @@ class EsParserH264 : public EsParser {
   bool ParseInternal();
 
   // Emit a frame if a frame has been started earlier.
-  void EmitFrameIfNeeded(int next_aud_pos);
+  // Returns true if successful, false if no PTS is available for the frame.
+  bool EmitFrameIfNeeded(int next_aud_pos);
 
   // Start a new frame.
   // Note: if aud_pos < 0, clear the current frame.