Fix trailing whitespace in .cpp, .h, and .idl files (ex. Source/core)

Source/web/WebHelperPluginImpl.cpp

 /*
  * Copyright (C) 2012 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 74 matching lines @@
         : m_widget(widget)
     {
         ASSERT(m_widget->m_widgetClient);
     }
 
 private:
     virtual void closeWindowSoon() OVERRIDE
     {
         // This should never be called since the only way to close the
         // invisible page is via closeHelperPlugin().
-        ASSERT_NOT_REACHED(); 
+        ASSERT_NOT_REACHED();
         m_widget->closeHelperPlugin();
     }
 
     virtual void* webView() const OVERRIDE
     {
         return m_widget->m_webView;
     }
 
     WebHelperPluginImpl* m_widget;
 };
@@ skipping 138 matching lines @@
     // A WebHelperPluginImpl instance usually has two references.
     //  - One owned by the instance itself. It represents the visible widget.
     //  - One owned by the hosting element. It's released when the hosting
     //    element asks the WebHelperPluginImpl to close.
     // We need them because the closing operation is asynchronous and the widget
     // can be closed while the hosting element is unaware of it.
     return adoptRef(new WebHelperPluginImpl(client)).leakRef();
 }
 
 } // namespace WebKit