Apply TypeChecking to MediaSource IDLs

Source/modules/mediasource/MediaSource.idl

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 10 matching lines @@
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+// https://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html#idl-def-MediaSource
+
 enum EndOfStreamError {
     "network",
     "decode"
 };
 
 [
     ActiveDOMObject,
     Constructor,
     ConstructorCallWith=ExecutionContext,
     RuntimeEnabled=MediaSource,
+    TypeChecking=Interface|Nullable|Unrestricted,
 ] interface MediaSource : EventTarget {
     // All the source buffers created by this object.
     readonly attribute SourceBufferList sourceBuffers;
 
     // Subset of sourceBuffers that provide data for the selected/enabled tracks.
     readonly attribute SourceBufferList activeSourceBuffers;
 
-    [RaisesException=Setter] attribute double duration;
+    [RaisesException=Setter] attribute unrestricted double duration;
 
     [RaisesException] SourceBuffer addSourceBuffer(DOMString type);
     [RaisesException] void removeSourceBuffer(SourceBuffer buffer);
 
     readonly attribute DOMString readyState;
 
     [RaisesException] void endOfStream(optional EndOfStreamError error);
 
     static boolean isTypeSupported (DOMString type);
 };