Remove duplicated headers from core/

Source/core/platform/graphics/filters/FEDropShadow.cpp

 /*
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
  * Copyright (C) 2013 Google 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/platform/graphics/filters/FEDropShadow.h"
 
 #include "core/platform/graphics/GraphicsContext.h"
 #include "core/platform/graphics/filters/FEGaussianBlur.h"
-#include "core/platform/graphics/filters/Filter.h"
 #include "platform/text/TextStream.h"
 #include "third_party/skia/include/core/SkColorFilter.h"
 #include "third_party/skia/include/effects/SkBlurImageFilter.h"
 
 using namespace std;
 
 namespace WebCore {
 
 FEDropShadow::FEDropShadow(Filter* filter, float stdX, float stdY, float dx, float dy, const Color& shadowColor, float shadowOpacity)
     : FilterEffect(filter)
@@ skipping 86 matching lines @@
 {
     writeIndent(ts, indent);
     ts << "[feDropShadow";
     FilterEffect::externalRepresentation(ts);
     ts << " stdDeviation=\"" << m_stdX << ", " << m_stdY << "\" dx=\"" << m_dx << "\" dy=\"" << m_dy << "\" flood-color=\"" << m_shadowColor.nameForRenderTreeAsText() <<"\" flood-opacity=\"" << m_shadowOpacity << "]\n";
     inputEffect(0)->externalRepresentation(ts, indent + 1);
     return ts;
 }
 
 } // namespace WebCore