Remove unused includes from core/{editing,fileapi,history,html}

Source/core/history/HistoryItem.cpp

 /*
  * Copyright (C) 2005, 2006, 2008, 2011 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 12 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
  */
 
 #include "config.h"
 #include "core/history/HistoryItem.h"
 
 #include <stdio.h>
 #include "bindings/v8/SerializedScriptValue.h"
 #include "core/dom/Document.h"
 #include "core/platform/network/ResourceRequest.h"
-#include <wtf/CurrentTime.h>
-#include <wtf/MathExtras.h>
-#include <wtf/text/CString.h>
+#include "wtf/CurrentTime.h"
+#include "wtf/text/CString.h"
 
 namespace WebCore {
 
 static long long generateSequenceNumber()
 {
     // Initialize to the current time to reduce the likelihood of generating
     // identifiers that overlap with those from past/future browser sessions.
     static long long next = static_cast<long long>(currentTime() * 1000000.0);
     return ++next;
 }
@@ skipping 439 matching lines @@
 } // namespace WebCore
 
 #ifndef NDEBUG
 
 int showTree(const WebCore::HistoryItem* item)
 {
     return item->showTree();
 }
 
 #endif