Bug 1505494 - remove redundant codes. r=cpearce

There are two exactly same codes here, remove one of them.

Differential Revision: https://phabricator.services.mozilla.com/D11502

--HG--
extra : moz-landing-system : lando

dom/media/AutoplayPolicy.cpp

@@ -167,12 +167,6 @@ IsMediaElementAllowedToPlay(const HTMLMediaElement& aElement)
     return true;
   }
 
-  if (!aElement.HasAudio() &&
-      aElement.ReadyState() >= HTMLMediaElement_Binding::HAVE_METADATA) {
-    AUTOPLAY_LOG("Allow media without audio track %p to autoplay\n", &aElement);
-    return true;
-  }
-
   return false;
 }