Introduce MIDIInputMap and MIDIOutputMap.

Source/bindings/core/v8/V8Binding.h

 /*
 * Copyright (C) 2009 Google Inc. All rights reserved.
 * Copyright (C) 2012 Ericsson AB. 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.
@@ skipping 942 matching lines @@
     ~V8RethrowTryCatchScope()
     {
         // ReThrow() is a no-op if no exception has been caught, so always call.
         m_block.ReThrow();
     }
 
 private:
     v8::TryCatch& m_block;
 };
 
+// Returns an object representing {done: true, value: undefined}.
+v8::Local<v8::Value> v8DoneIteratorResult(v8::Isolate*);
+
+// Returns an object representing {done: false, value: |value|}.
+v8::Local<v8::Value> v8IteratorResult(v8::Isolate*, v8::Handle<v8::Value>);
+template <typename T>
+v8::Local<v8::Value> v8IteratorResult(ScriptState* scriptState, const T& value)
+{
+    return v8IteratorResult(scriptState->isolate(), V8ValueTraits<T>::toV8Value(value, scriptState->context()->Global(), scriptState->isolate()));
+}
+
 } // namespace blink
 
 #endif // V8Binding_h