Add JSON serializer to MediaDeviceInfo.

third_party/WebKit/Source/modules/mediastream/MediaDeviceInfo.h

 /*
  * Copyright (C) 2014 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:
  * 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 15 matching lines @@
 #ifndef MediaDeviceInfo_h
 #define MediaDeviceInfo_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "modules/ModulesExport.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/WebMediaDeviceInfo.h"
 
 namespace blink {
 
+class ScriptState;
+class ScriptValue;
+
 class MODULES_EXPORT MediaDeviceInfo final : public GarbageCollectedFinalized<MediaDeviceInfo>, public ScriptWrappable {
     DEFINE_WRAPPERTYPEINFO();
 public:
     static MediaDeviceInfo* create(const WebMediaDeviceInfo&);
 
     String deviceId() const;
     String kind() const;
     String label() const;
     String groupId() const;
 
+    ScriptValue toJSONForBinding(ScriptState*);
+
     DEFINE_INLINE_TRACE() { }
 
 private:
     explicit MediaDeviceInfo(const WebMediaDeviceInfo&);
 
     WebMediaDeviceInfo m_webMediaDeviceInfo;
 };
 
 typedef HeapVector<Member<MediaDeviceInfo>> MediaDeviceInfoVector;
 
 } // namespace blink
 
 #endif // MediaDeviceInfo_h