Remove duplicated headers from core/

Source/core/loader/MixedContentChecker.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:
  *
  * 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
@@ skipping 17 matching lines @@
 
 #include "config.h"
 #include "core/loader/MixedContentChecker.h"
 
 #include "core/dom/Document.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/frame/Frame.h"
 #include "core/page/Settings.h"
 #include "platform/weborigin/SecurityOrigin.h"
-#include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
 MixedContentChecker::MixedContentChecker(Frame* frame)
     : m_frame(frame)
 {
 }
 
 FrameLoaderClient* MixedContentChecker::client() const
 {
@@ skipping 41 matching lines @@
 }
 
 void MixedContentChecker::logWarning(bool allowed, const String& action, const KURL& target) const
 {
     String message = String(allowed ? "" : "[blocked] ") + "The page at '" + m_frame->document()->url().elidedString() + "' was loaded over HTTPS, but " + action + " insecure content from '" + target.elidedString() + "': this content should also be loaded over HTTPS.\n";
     MessageLevel messageLevel = allowed ? WarningMessageLevel : ErrorMessageLevel;
     m_frame->document()->addConsoleMessage(SecurityMessageSource, messageLevel, message);
 }
 
 } // namespace WebCore