Add support for avc3 codec string.

content/renderer/media/crypto/key_systems.cc

Index: content/renderer/media/crypto/key_systems.cc
diff --git a/content/renderer/media/crypto/key_systems.cc b/content/renderer/media/crypto/key_systems.cc
index 5b6397145a6bc2a857c500b18841bd9a436a555c..3cd93853171bbc955d079a8b29768f1a77d2dbd3 100644
--- a/content/renderer/media/crypto/key_systems.cc
+++ b/content/renderer/media/crypto/key_systems.cc
@@ -36,7 +36,7 @@ const char kVorbisVP8[] = "vorbis,vp8,vp8.0";
 const char kAudioMp4[] = "audio/mp4";
 const char kVideoMp4[] = "video/mp4";
 const char kMp4a[] = "mp4a";
-const char kMp4aAvc1[] = "mp4a,avc1";
+const char kMp4aAvc1Avc3[] = "mp4a,avc1,avc3";
 #endif  // defined(USE_PROPRIETARY_CODECS)
 
 static void AddClearKey(std::vector<KeySystemInfo>* concrete_key_systems) {
@@ -46,7 +46,7 @@ static void AddClearKey(std::vector<KeySystemInfo>* concrete_key_systems) {
   info.supported_types.push_back(std::make_pair(kVideoWebM, kVorbisVP8));
 #if defined(USE_PROPRIETARY_CODECS)
   info.supported_types.push_back(std::make_pair(kAudioMp4, kMp4a));
-  info.supported_types.push_back(std::make_pair(kVideoMp4, kMp4aAvc1));
+  info.supported_types.push_back(std::make_pair(kVideoMp4, kMp4aAvc1Avc3));
 #endif  // defined(USE_PROPRIETARY_CODECS)
 
   info.use_aes_decryptor = true;