Enable vp09 codec string in WebM by default

media/base/mime_util_internal.cc

Index: media/base/mime_util_internal.cc
diff --git a/media/base/mime_util_internal.cc b/media/base/mime_util_internal.cc
index b486fd9a6139f470621e9d41cf61a8d873260292..14d4486bb9d10542cd99eab640fb00aa6b8b0725 100644
--- a/media/base/mime_util_internal.cc
+++ b/media/base/mime_util_internal.cc
@@ -93,8 +93,7 @@ static bool ParseVp9CodecID(const std::string& mime_type_lower_case,
     return ParseNewStyleVp9CodecID(codec_id, out_profile, out_level,
                                    out_color_space);
   } else if (mime_type_lower_case == "video/webm") {
-    if (HasNewVp9CodecStringSupport() &&
-        ParseNewStyleVp9CodecID(codec_id, out_profile, out_level,
+    if (ParseNewStyleVp9CodecID(codec_id, out_profile, out_level,
                                 out_color_space)) {
       return true;
     }
@@ -873,10 +872,12 @@ SupportsType MimeUtil::IsCodecSupported(const std::string& mime_type_lower_case,
       default:
         ambiguous_platform_support = true;
     }
-  } else if (codec == MimeUtil::VP9 && video_profile != VP9PROFILE_PROFILE0) {
-    // We don't know if the underlying platform supports these profiles. Need
-    // to add platform level querying to get supported profiles.
-    // https://crbug.com/604566
+  } else if (codec == MimeUtil::VP9 && video_profile != VP9PROFILE_PROFILE0 &&
+             is_encrypted) {
+    // LibVPX is not generally used for encrypted videos, so we do not know
+    // whether higher profiles are supported.
+    // TODO(chcunningham/xhwang): Add details to indicate which key system will
+    // be used and check support by querying the matching KeySystemProperties.
     ambiguous_platform_support = true;
   }