Decouple MIDIAccess initialization from MIDIAccess class.

Source/modules/webmidi/MIDIController.h

 /*
  * 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 18 matching lines @@
  */
 
 #ifndef MIDIController_h
 #define MIDIController_h
 
 #include "core/page/Page.h"
 #include "platform/heap/Handle.h"
 
 namespace WebCore {
 
-class MIDIAccess;
+class MIDIAccessInitializer;
 class MIDIClient;
 
 class MIDIController FINAL : public NoBaseWillBeGarbageCollectedFinalized<MIDIController>, public WillBeHeapSupplement<Page> {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(MIDIController);
 public:
     virtual ~MIDIController();
 
-    void requestSysexPermission(PassRefPtrWillBeRawPtr<MIDIAccess>);
-    void cancelSysexPermissionRequest(MIDIAccess*);
+    void requestSysexPermission(MIDIAccessInitializer*);
+    void cancelSysexPermissionRequest(MIDIAccessInitializer*);
 
     static PassOwnPtrWillBeRawPtr<MIDIController> create(PassOwnPtr<MIDIClient>);
     static const char* supplementName();
     static MIDIController* from(Page* page) { return static_cast<MIDIController*>(WillBeHeapSupplement<Page>::from(page, supplementName())); }
 
     virtual void trace(Visitor* visitor) OVERRIDE { WillBeHeapSupplement<Page>::trace(visitor); }
 
 protected:
     explicit MIDIController(PassOwnPtr<MIDIClient>);
 
 private:
     OwnPtr<MIDIClient> m_client;
 };
 
 } // namespace WebCore
 
 #endif // MIDIController_h