diff -up chromium-62.0.3192.0/media/base/audio_codecs.cc.extra-media chromium-62.0.3192.0/media/base/audio_codecs.cc
--- chromium-62.0.3192.0/media/base/audio_codecs.cc.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/base/audio_codecs.cc	2017-08-30 15:39:09.735186077 +0200
@@ -46,6 +46,10 @@ std::string GetCodecName(AudioCodec code
       return "ac3";
     case kCodecMpegHAudio:
       return "mpeg-h-audio";
+    case kCodecMP2:
+      return "mp2";
+    case kCodecDTS:
+      return "dts";
   }
   NOTREACHED();
   return "";
@@ -72,6 +74,10 @@ AudioCodec StringToAudioCodec(const std:
     return kCodecVorbis;
   if (base::StartsWith(codec_id, "mp4a.40.", base::CompareCase::SENSITIVE))
     return kCodecAAC;
+  if (codec_id == "mp2")
+    return kCodecMP2;
+  if (codec_id == "dts")
+    return kCodecDTS;
   return kUnknownAudioCodec;
 }
 
diff -up chromium-62.0.3192.0/media/base/audio_codecs.h.extra-media chromium-62.0.3192.0/media/base/audio_codecs.h
--- chromium-62.0.3192.0/media/base/audio_codecs.h.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/base/audio_codecs.h	2017-08-30 15:39:09.735186077 +0200
@@ -33,13 +33,15 @@
   kCodecALAC = 15,
   kCodecAC3 = 16,
   kCodecMpegHAudio = 17,
+  kCodecMP2 = 18,
+  kCodecDTS = 19,
   // DO NOT ADD RANDOM AUDIO CODECS!
   //
   // The only acceptable time to add a new codec is if there is production code
   // that uses said codec in the same CL.
 
   // Must always be equal to the largest entry ever logged.
-  kAudioCodecMax = kCodecMpegHAudio,
+  kAudioCodecMax = kCodecDTS,
 };
 
 std::string MEDIA_EXPORT GetCodecName(AudioCodec codec);
diff -up chromium-62.0.3192.0/media/base/mime_util_internal.cc.extra-media chromium-62.0.3192.0/media/base/mime_util_internal.cc
--- chromium-62.0.3192.0/media/base/mime_util_internal.cc.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/base/mime_util_internal.cc	2017-08-30 15:44:46.519076991 +0200
@@ -87,6 +87,10 @@
       {"vp8", MimeUtil::VP8},
       {"vp8.0", MimeUtil::VP8},
       {"theora", MimeUtil::THEORA},
+      {"dts", MimeUtil::DTS},
+      {"mp2", MimeUtil::MP2},
+      {"mp4v.20.8", MimeUtil::MPEG4_SP},
+      {"mp4v.20.240", MimeUtil::MPEG4_ASP},
   });
 
   return *kStringToCodecMap;
@@ -162,6 +166,10 @@
       return kCodecOpus;
     case MimeUtil::FLAC:
       return kCodecFLAC;
+    case MimeUtil::DTS:
+      return kCodecDTS;
+    case MimeUtil::MP2:
+      return kCodecMP2;
     default:
       break;
   }
@@ -184,6 +192,9 @@
       return kCodecTheora;
     case MimeUtil::DOLBY_VISION:
       return kCodecDolbyVision;
+    case MimeUtil::MPEG4_SP:
+    case MimeUtil::MPEG4_ASP:
+      return kCodecMPEG4;
     default:
       break;
   }
@@ -274,6 +285,35 @@
   CodecSet ogg_codecs(ogg_audio_codecs);
   ogg_codecs.insert(ogg_video_codecs.begin(), ogg_video_codecs.end());
 
+  CodecSet matroska_audio_codecs;
+  matroska_audio_codecs.emplace(OPUS);
+  matroska_audio_codecs.emplace(VORBIS);
+  matroska_audio_codecs.emplace(AC3);
+  matroska_audio_codecs.emplace(EAC3);
+  matroska_audio_codecs.emplace(DTS);
+  matroska_audio_codecs.emplace(MP3);
+  matroska_audio_codecs.emplace(MP2);
+  matroska_audio_codecs.emplace(MPEG2_AAC);
+  matroska_audio_codecs.emplace(MPEG4_AAC);
+  matroska_audio_codecs.emplace(PCM);
+  matroska_audio_codecs.emplace(FLAC);
+
+  CodecSet matroska_video_codecs;
+  matroska_video_codecs.emplace(THEORA);
+  matroska_video_codecs.emplace(VP8);
+  matroska_video_codecs.emplace(VP9);
+  matroska_video_codecs.emplace(H264);
+  matroska_video_codecs.emplace(MPEG4_SP);
+  matroska_video_codecs.emplace(MPEG4_ASP);
+#if BUILDFLAG(ENABLE_AV1_DECODER)
+  matroska_video_codecs.emplace(AV1);
+#endif
+#if BUILDFLAG(ENABLE_HEVC_DEMUXING)
+  matroska_video_codecs.emplace(HEVC);
+#endif  // BUILDFLAG(ENABLE_HEVC_DEMUXING)
+  CodecSet matroska_codecs(matroska_audio_codecs);
+  matroska_codecs.insert(matroska_video_codecs.begin(), matroska_video_codecs.end());
+
   const CodecSet webm_audio_codecs{OPUS, VORBIS};
   CodecSet webm_video_codecs{VP8, VP9};
 #if BUILDFLAG(ENABLE_AV1_DECODER)
@@ -283,9 +323,9 @@
   CodecSet webm_codecs(webm_audio_codecs);
   webm_codecs.insert(webm_video_codecs.begin(), webm_video_codecs.end());
 
-  const CodecSet mp3_codecs{MP3};
+  const CodecSet mp3_codecs{MP3, MP2};
 
-  CodecSet mp4_audio_codecs{FLAC, MP3, OPUS};
+  CodecSet mp4_audio_codecs{FLAC, MP3, OPUS, MP2, DTS, AC3, EAC3};
 
   // Only VP9 with valid codec string vp09.xx.xx.xx.xx.xx.xx.xx is supported.
   // See ParseVp9CodecID for details.
@@ -309,6 +349,8 @@
 #endif  // BUILDFLAG(ENABLE_MPEG_H_AUDIO_DEMUXING)
 
   mp4_video_codecs.emplace(H264);
+  mp4_video_codecs.emplace(MPEG4_SP);
+  mp4_video_codecs.emplace(MPEG4_ASP);
 #if BUILDFLAG(ENABLE_HEVC_DEMUXING)
   mp4_video_codecs.emplace(HEVC);
 #endif  // BUILDFLAG(ENABLE_HEVC_DEMUXING)
@@ -345,6 +387,10 @@
   DCHECK(!mp4_video_codecs.empty());
   AddContainerWithCodecs("video/mp4", mp4_codecs);
 
+  AddContainerWithCodecs("audio/x-matroska", matroska_audio_codecs);
+  AddContainerWithCodecs("video/x-matroska", matroska_codecs);
+  AddContainerWithCodecs("video/x-msvideo", matroska_codecs);
+
 #if BUILDFLAG(USE_PROPRIETARY_CODECS)
   AddContainerWithCodecs("audio/aac", implicit_codec);  // AAC / ADTS.
   // These strings are supported for backwards compatibility only and thus only
diff -up chromium-62.0.3192.0/media/base/mime_util_internal.h.extra-media chromium-62.0.3192.0/media/base/mime_util_internal.h
--- chromium-62.0.3192.0/media/base/mime_util_internal.h.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/base/mime_util_internal.h	2017-08-30 15:39:09.734186095 +0200
@@ -46,7 +46,11 @@ class MEDIA_EXPORT MimeUtil {
     DOLBY_VISION,
     AV1,
     MPEG_H_AUDIO,
-    LAST_CODEC = MPEG_H_AUDIO
+    DTS,
+    MP2,
+    MPEG4_SP,
+    MPEG4_ASP,
+    LAST_CODEC = MPEG4_ASP
   };
 
   // Platform configuration structure.  Controls which codecs are supported at
diff -up chromium-62.0.3192.0/media/ffmpeg/ffmpeg_common.cc.extra-media chromium-62.0.3192.0/media/ffmpeg/ffmpeg_common.cc
--- chromium-62.0.3192.0/media/ffmpeg/ffmpeg_common.cc.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/ffmpeg/ffmpeg_common.cc	2017-08-30 15:39:09.735186077 +0200
@@ -115,6 +115,10 @@ AudioCodec CodecIDToAudioCodec(AVCodecID
       return kCodecOpus;
     case AV_CODEC_ID_ALAC:
       return kCodecALAC;
+    case AV_CODEC_ID_MP2:
+      return kCodecMP2;
+    case AV_CODEC_ID_DTS:
+      return kCodecDTS;
     default:
       DVLOG(1) << "Unknown audio CodecID: " << codec_id;
   }
@@ -166,6 +168,14 @@ AVCodecID AudioCodecToCodecID(AudioCodec
       return AV_CODEC_ID_PCM_MULAW;
     case kCodecOpus:
       return AV_CODEC_ID_OPUS;
+    case kCodecAC3:
+      return AV_CODEC_ID_AC3;
+    case kCodecEAC3:
+      return AV_CODEC_ID_EAC3;
+    case kCodecMP2:
+      return AV_CODEC_ID_MP2;
+    case kCodecDTS:
+      return AV_CODEC_ID_DTS;
     default:
       DVLOG(1) << "Unknown AudioCodec: " << audio_codec;
   }
@@ -389,23 +389,6 @@ bool AVCodecContextToAudioDecoderConfig(
                                                codec_context->channels);
 
   int sample_rate = codec_context->sample_rate;
-  switch (codec) {
-    // For AC3/EAC3 we enable only demuxing, but not decoding, so FFmpeg does
-    // not fill |sample_fmt|.
-    case kCodecAC3:
-    case kCodecEAC3:
-#if BUILDFLAG(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
-      // The spec for AC3/EAC3 audio is ETSI TS 102 366. According to sections
-      // F.3.1 and F.5.1 in that spec the sample_format for AC3/EAC3 must be 16.
-      sample_format = kSampleFormatS16;
-#else
-      NOTREACHED();
-#endif
-      break;
-
-    default:
-      break;
-  }
 
   base::TimeDelta seek_preroll;
   if (codec_context->seek_preroll > 0) {
@@ -435,13 +418,6 @@ bool AVCodecContextToAudioDecoderConfig(
   if (channel_layout == CHANNEL_LAYOUT_DISCRETE)
     config->SetChannelsForDiscrete(codec_context->channels);
 
-#if BUILDFLAG(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
-  // These are bitstream formats unknown to ffmpeg, so they don't have
-  // a known sample format size.
-  if (codec == kCodecAC3 || codec == kCodecEAC3)
-    return true;
-#endif
-
   // Verify that AudioConfig.bits_per_channel was calculated correctly for
   // codecs that have |sample_fmt| set by FFmpeg.
   DCHECK_EQ(av_get_bytes_per_sample(codec_context->sample_fmt) * 8,
diff -up chromium-62.0.3192.0/media/filters/ffmpeg_video_decoder.cc.extra-media chromium-62.0.3192.0/media/filters/ffmpeg_video_decoder.cc
--- chromium-62.0.3192.0/media/filters/ffmpeg_video_decoder.cc.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/filters/ffmpeg_video_decoder.cc	2017-08-30 15:39:09.736186059 +0200
@@ -38,7 +38,6 @@
     case kUnknownVideoCodec:
     case kCodecVC1:
     case kCodecMPEG2:
-    case kCodecHEVC:
     case kCodecVP9:
     case kCodecAV1:
     case kCodecDolbyVision:
@@ -52,6 +51,7 @@
 
     case kCodecH264:
     case kCodecVP8:
+    case kCodecHEVC:
       // Normalize to three threads for 1080p content, then scale linearly
       // with number of pixels.
       // Examples:
diff -up chromium-62.0.3192.0/media/remoting/proto_enum_utils.cc.extra-media chromium-62.0.3192.0/media/remoting/proto_enum_utils.cc
--- chromium-62.0.3192.0/media/remoting/proto_enum_utils.cc.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/remoting/proto_enum_utils.cc	2017-08-30 15:39:09.736186059 +0200
@@ -58,6 +58,8 @@ base::Optional<AudioCodec> ToMediaAudioC
     CASE_RETURN_OTHER(kCodecALAC);
     CASE_RETURN_OTHER(kCodecAC3);
     CASE_RETURN_OTHER(kCodecMpegHAudio);
+    CASE_RETURN_OTHER(kCodecMP2);
+    CASE_RETURN_OTHER(kCodecDTS);
   }
   return base::nullopt;  // Not a 'default' to ensure compile-time checks.
 }
@@ -85,6 +86,8 @@ base::Optional<pb::AudioDecoderConfig::C
     CASE_RETURN_OTHER(kCodecALAC);
     CASE_RETURN_OTHER(kCodecAC3);
     CASE_RETURN_OTHER(kCodecMpegHAudio);
+    CASE_RETURN_OTHER(kCodecMP2);
+    CASE_RETURN_OTHER(kCodecDTS);
   }
   return base::nullopt;  // Not a 'default' to ensure compile-time checks.
 }
diff -up chromium-62.0.3192.0/media/remoting/media_remoting_rpc.proto.extra-media chromium-62.0.3192.0/media/remoting/media_remoting_rpc.proto
--- chromium-62.0.3192.0/media/remoting/media_remoting_rpc.proto.extra-media	2017-08-22 21:04:45.000000000 +0200
+++ chromium-62.0.3192.0/media/remoting/media_remoting_rpc.proto	2017-08-30 15:39:09.736186059 +0200
@@ -67,6 +67,8 @@ message AudioDecoderConfig {
     kCodecALAC = 15;
     kCodecAC3 = 16;
     kCodecMpegHAudio = 17;
+    kCodecMP2 = 18;
+    kCodecDTS = 19;
   }
 
   // Proto version of media::SampleFormat.
diff -up chromium-62.0.3192.0/net/base/mime_util.cc.extra-media chromium-62.0.3192.0/net/base/mime_util.cc
--- chromium-62.0.3192.0/net/base/mime_util.cc.extra-media	2017-08-22 21:04:46.000000000 +0200
+++ chromium-62.0.3192.0/net/base/mime_util.cc	2017-08-30 15:47:23.952221630 +0200
@@ -94,6 +94,9 @@
     {"image/png", "png"},
     {"image/apng", "png"},
     {"image/webp", "webp"},
+    {"video/x-matroska", "mkv"},
+    {"audio/x-matroska", "mkv"},
+    {"video/x-msvideo", "avi"},
     {"multipart/related", "mht,mhtml"},
     {"text/css", "css"},
     {"text/html", "html,htm,shtml,shtm"},
@@ -495,6 +498,7 @@
   "audio/vorbis",
   "audio/wav",
   "audio/webm",
+  "audio/x-matroska",
   "audio/x-m4a",
   "audio/x-ms-wma",
   "audio/vnd.rn-realaudio",
@@ -512,8 +516,10 @@
   "video/webm",
   "video/x-dv",
   "video/x-m4v",
+  "video/x-matroska",
   "video/x-mpeg",
   "video/x-ms-asf",
+  "video/x-msvideo",
   "video/x-ms-wmv"
 };
 
--- chromium-73.0.3683.75/media/base/supported_types.cc.extra-media	2019-03-11 23:00:59.000000000 +0100
+++ chromium-73.0.3683.75/media/base/supported_types.cc	2019-03-17 18:40:07.610556592 +0100
@@ -144,6 +144,7 @@ bool IsAudioCodecProprietary(AudioCodec
     case media::kCodecAAC:
     case media::kCodecAC3:
     case media::kCodecEAC3:
+    case media::kCodecDTS:
     case media::kCodecAMR_NB:
     case media::kCodecAMR_WB:
     case media::kCodecGSM_MS:
@@ -152,6 +153,7 @@ bool IsAudioCodecProprietary(AudioCodec
       return true;
 
     case media::kCodecFLAC:
+    case media::kCodecMP2:
     case media::kCodecMP3:
     case media::kCodecOpus:
     case media::kCodecVorbis:
@@ -174,6 +176,7 @@ bool IsDefaultSupportedAudioType(const A
   switch (type.codec) {
     case media::kCodecAAC:
     case media::kCodecFLAC:
+    case media::kCodecMP2:
     case media::kCodecMP3:
     case media::kCodecOpus:
     case media::kCodecPCM:
@@ -182,6 +185,10 @@ bool IsDefaultSupportedAudioType(const A
     case media::kCodecPCM_S24BE:
     case media::kCodecPCM_ALAW:
     case media::kCodecVorbis:
+    case media::kCodecEAC3:
+    case media::kCodecALAC:
+    case media::kCodecAC3:
+    case media::kCodecDTS:
       return true;
 
     case media::kCodecAMR_NB:
@@ -193,9 +200,6 @@ bool IsDefaultSupportedAudioType(const A
       return false;
 #endif
 
-    case media::kCodecEAC3:
-    case media::kCodecALAC:
-    case media::kCodecAC3:
     case media::kCodecMpegHAudio:
     case media::kUnknownAudioCodec:
       return false;
@@ -245,21 +245,15 @@
     case media::kCodecH264:
     case media::kCodecVP8:
     case media::kCodecTheora:
-      return true;
-
-    case media::kUnknownVideoCodec:
     case media::kCodecVC1:
     case media::kCodecMPEG2:
+    case media::kCodecMPEG4:
     case media::kCodecHEVC:
-    case media::kCodecDolbyVision:
-      return false;
-
-    case media::kCodecMPEG4:
-#if defined(OS_CHROMEOS)
       return true;
-#else
+
+    case media::kUnknownVideoCodec:
+    case media::kCodecDolbyVision:
       return false;
-#endif
   }
 
   NOTREACHED();