Remove unnecessary Document.h includes in .cpp files

Source/core/fetch/MemoryCache.cpp

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2004, 2005, 2006, 2007, 2008 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.
 
     This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Library General Public License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to
     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
 */
 
 #include "config.h"
 #include "core/fetch/MemoryCache.h"
 
 #include "core/dom/CrossThreadTask.h"
-#include "core/dom/Document.h"
 #include "core/fetch/ResourcePtr.h"
 #include "core/frame/FrameView.h"
 #include "core/workers/WorkerGlobalScope.h"
 #include "core/workers/WorkerLoaderProxy.h"
 #include "core/workers/WorkerThread.h"
 #include "platform/Logging.h"
 #include "platform/TraceEvent.h"
 #include "platform/weborigin/SecurityOrigin.h"
 #include "platform/weborigin/SecurityOriginHash.h"
 #include "public/platform/Platform.h"
@@ skipping 682 matching lines @@
                 printf("(%.1fK, %.1fK, %uA, %dR, %d, %d); ", current->decodedSize() / 1024.0f, (current->encodedSize() + current->overheadSize()) / 1024.0f, current->accessCount(), current->hasClients(), current->isPurgeable(), current->wasPurged());
 
             current = prev;
         }
     }
 }
 
 #endif // MEMORY_CACHE_STATS
 
 } // namespace WebCore