Extract supported codecs from CDM component manifest.

third_party/widevine/cdm/widevine_cdm_common.h

Index: third_party/widevine/cdm/widevine_cdm_common.h
diff --git a/third_party/widevine/cdm/widevine_cdm_common.h b/third_party/widevine/cdm/widevine_cdm_common.h
index 2b3ef0dbb653038210b2bb9304bd079c945640d9..70a327cda666d990089a16555e30fc1575566cca 100644
--- a/third_party/widevine/cdm/widevine_cdm_common.h
+++ b/third_party/widevine/cdm/widevine_cdm_common.h
@@ -45,6 +45,15 @@ const char kWidevineCdmAdapterFileName[] =
     "libwidevinecdmadapter.so";
 #endif
 
+// The following strings are used to communicate supported codecs (from the
+// component manifest) via WebPluginInfo::WebPluginMimeType's additional params.
+const char kCdmSupportedCodecsParamName[] = "codecs";
+const char kCdmSupportedCodecVorbis[] = "vorbis";
+const char kCdmSupportedCodecVp8[] = "vp8";
+#if defined(USE_PROPRIETARY_CODECS)
+const char kCdmSupportedCodecAac[] = "aac";
+const char kCdmSupportedCodecAvc1[] = "avc1";
+#endif  // defined(USE_PROPRIETARY_CODECS)
 
 #if defined(OS_MACOSX) || defined(OS_WIN)
 // CDM is installed by the component installer instead of the Chrome installer.