Remove some dead code from html/

Source/core/html/HTMLPlugInElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 108 matching lines @@
     virtual RenderWidget* existingRenderWidget() const = 0;
     virtual void updateWidgetInternal() = 0;
 
     enum DisplayState {
         Restarting,
         RestartingWithPendingMouseClick,
         Playing
     };
     DisplayState displayState() const { return m_displayState; }
     void setDisplayState(DisplayState state) { m_displayState = state; }
-    const String loadedMimeType() const;
     bool loadPlugin(const KURL&, const String& mimeType, const Vector<String>& paramNames, const Vector<String>& paramValues, bool useFallback, bool requireRenderer);
     bool pluginIsLoadable(const KURL&, const String& mimeType);
     bool wouldLoadAsNetscapePlugin(const String& url, const String& serviceType);
 
     mutable RefPtr<SharedPersistent<v8::Object> > m_pluginWrapper;
     NPObject* m_NPObject;
     bool m_isCapturingMouseEvents;
     bool m_needsWidgetUpdate;
     bool m_shouldPreferPlugInsForImages;
     DisplayState m_displayState;
@@ skipping 14 matching lines @@
 inline bool isHTMLPlugInElement(const HTMLElement& element)
 {
     return element.isPluginElement();
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(HTMLPlugInElement);
 
 } // namespace WebCore
 
 #endif // HTMLPlugInElement_h