Ensure that the controls attribute is correctly reflected in JS.

Source/core/html/HTMLMediaElement.idl

 /*
  * Copyright (C) 2007, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 58 matching lines @@
     [Reflect] attribute boolean autoplay;
     [Reflect] attribute boolean loop;
     void play();
     void pause();
 
     // media controller
     [RuntimeEnabled=MediaController, Reflect] attribute DOMString mediaGroup;
     [RuntimeEnabled=MediaController, TypeChecking=Interface] attribute MediaController? controller;
 
     // controls
-    attribute boolean controls;
+    [Reflect] attribute boolean controls;
     [RaisesException=Setter] attribute double volume;
     attribute boolean muted;
     [Reflect=muted] attribute boolean defaultMuted;
 
     // tracks
     [RuntimeEnabled=AudioVideoTracks] readonly attribute AudioTrackList audioTracks;
     [RuntimeEnabled=AudioVideoTracks] readonly attribute VideoTrackList videoTracks;
     readonly attribute TextTrackList textTracks;
     [RaisesException] TextTrack addTextTrack(DOMString kind, optional DOMString label, optional DOMString language);
 
     // WebKit extensions
 
     // The number of bytes consumed by the media decoder.
     [MeasureAs=PrefixedAudioDecodedByteCount] readonly attribute unsigned long webkitAudioDecodedByteCount;
     [MeasureAs=PrefixedVideoDecodedByteCount] readonly attribute unsigned long webkitVideoDecodedByteCount;
 
     [Reflect, RuntimeEnabled=SubresourceIntegrity] attribute DOMString integrity;
 };