Support EAC3 (Dolby Digital Plus) codec

media/filters/stream_parser_factory.cc

Index: media/filters/stream_parser_factory.cc
diff --git a/media/filters/stream_parser_factory.cc b/media/filters/stream_parser_factory.cc
index 93b0e8b3d53da4e02feb345497dbbe4aea075216..8f4a55fe79de9b2f431fc751d9032ebd05cea39e 100644
--- a/media/filters/stream_parser_factory.cc
+++ b/media/filters/stream_parser_factory.cc
@@ -108,6 +108,12 @@ static const CodecInfo kMPEG2AACLCCodecInfo = {
   "mp4a.67", CodecInfo::AUDIO, NULL
 };
 
+#if defined(ENABLE_EAC3_PLAYBACK)
+static const CodecInfo kEAC3CodecInfo = {
+  "mp4a.a6", CodecInfo::AUDIO, NULL
+};
+#endif
+
 static const CodecInfo* kVideoMP4Codecs[] = {
   &kH264CodecInfo,
   &kMPEG4AACCodecInfo,
@@ -118,6 +124,9 @@ static const CodecInfo* kVideoMP4Codecs[] = {
 static const CodecInfo* kAudioMP4Codecs[] = {
   &kMPEG4AACCodecInfo,
   &kMPEG2AACLCCodecInfo,
+#if defined(ENABLE_EAC3_PLAYBACK)
+  &kEAC3CodecInfo,
+#endif
   NULL
 };
 
@@ -125,6 +134,10 @@ static media::StreamParser* BuildMP4Parser(
     const std::vector<std::string>& codecs, const media::LogCB& log_cb) {
   std::set<int> audio_object_types;
   bool has_sbr = false;
+#if defined(ENABLE_EAC3_PLAYBACK)
+  bool enable_eac3 = CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kEnableEac3Playback);
+#endif
   for (size_t i = 0; i < codecs.size(); ++i) {
     std::string codec_id = codecs[i];
     if (MatchPattern(codec_id, kMPEG2AACLCCodecInfo.pattern)) {
@@ -139,6 +152,10 @@ static media::StreamParser* BuildMP4Parser(
         has_sbr = true;
         break;
       }
+#if defined(ENABLE_EAC3_PLAYBACK)
+    } else if (enable_eac3 && MatchPattern(codec_id, kEAC3CodecInfo.pattern)) {
+      audio_object_types.insert(media::mp4::kEAC3);
+#endif
     }
   }
 
@@ -204,6 +221,12 @@ static bool IsSupported(const std::string& type,
         const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
         switch (codec_type) {
           case CodecInfo::AUDIO:
+#if defined(ENABLE_EAC3_PLAYBACK)
+            if (MatchPattern(codec_id, kEAC3CodecInfo.pattern) &&
+                !cmd_line->HasSwitch(switches::kEnableEac3Playback)) {
+              return false;
+            }
+#endif
             *has_audio = true;
             break;
           case CodecInfo::VIDEO: