Media: Do not support new codecs with legacy MIME type names.

media/base/mime_util_internal.h

Index: media/base/mime_util_internal.h
diff --git a/media/base/mime_util_internal.h b/media/base/mime_util_internal.h
index 5e06b54fc8b3fbd944e2e99113a5647d2471ad11..1f72192ba5fd28fed5df952ea4afe3137704b8e9 100644
--- a/media/base/mime_util_internal.h
+++ b/media/base/mime_util_internal.h
@@ -87,9 +87,13 @@ class MEDIA_EXPORT MimeUtil {
   };
   typedef std::map<std::string, CodecEntry> StringToCodecMappings;
 
-  // For faster lookup, keep hash sets.
+  // Initializes the supported media types into hash sets for faster lookup.
   void InitializeMimeTypeMaps();
 
+  // Adds |mime_type| with the specified codecs to |media_format_map_|.
+  void AddContainerWithCodecs(const std::string& mime_type,
+                              const std::string& codecs_list);
+
   // Returns IsSupported if all codec IDs in |codecs| are unambiguous and are
   // supported in |mime_type_lower_case|. MayBeSupported is returned if at least
   // one codec ID in |codecs| is ambiguous but all the codecs are supported.