Refactoring: toPluginView and toPluginDocument implemented but not used.

Source/core/html/PluginDocument.cpp

 /*
  * Copyright (C) 2006, 2008 Apple 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 125 matching lines @@
             view->didFinishLoading();
         else
             view->didFailLoading(error);
         m_embedElement = 0;
     }
     RawDataDocumentParser::finish();
 }
 
 PluginView* PluginDocumentParser::pluginView() const
 {
-    if (Widget* widget = static_cast<PluginDocument*>(document())->pluginWidget()) {
+    if (Widget* widget = toPluginDocument(document())->pluginWidget()) {
         ASSERT_WITH_SECURITY_IMPLICATION(widget->isPluginContainer());
-        return static_cast<PluginView*>(widget);
+        return toPluginView(widget);
     }
     return 0;
 }
 
 PluginDocument::PluginDocument(const DocumentInit& initializer)
     : HTMLDocument(initializer, PluginDocumentClass)
     , m_shouldLoadPluginManually(true)
 {
     setCompatibilityMode(QuirksMode);
     lockCompatibilityMode();
@@ skipping 31 matching lines @@
     // with how many times we call beforeload on object elements. <rdar://problem/8441094>.
     if (!shouldLoadPluginManually())
         return;
 
     DocumentLoader* documentLoader = frame()->loader()->activeDocumentLoader();
     documentLoader->cancelMainResourceLoad(ResourceError::cancelledError(documentLoader->request().url()));
     setShouldLoadPluginManually(false);
 }
 
 }