Disable mute/unmute when media does not have an audio track.

webkit/glue/context_menu_client_impl.cc

Index: webkit/glue/context_menu_client_impl.cc
diff --git a/webkit/glue/context_menu_client_impl.cc b/webkit/glue/context_menu_client_impl.cc
index b32b572cf68cccdf6abdf7e37a83fc6626417856..ca2dee8b851b026a6960cb10c794292f790fd61b 100644
--- a/webkit/glue/context_menu_client_impl.cc
+++ b/webkit/glue/context_menu_client_impl.cc
@@ -207,6 +207,8 @@ WebCore::PlatformMenuDescription
     if (media_element->supportsSave()) {
       media_params.player_state |= ContextMenuMediaParams::CAN_SAVE;
     }
+
+    media_params.has_audio = media_element->hasAudio();
   }
 
   // If it's not a link, an image, a media element, or an image/media link,