Clean up includes and forward-declarations in the flowthread / multicol files.

Source/core/rendering/RenderMultiColumnSet.cpp

 /*
  * Copyright (C) 2012 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
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/rendering/RenderMultiColumnSet.h"
 
-#include "core/paint/BoxPainter.h"
 #include "core/paint/MultiColumnSetPainter.h"
-#include "core/paint/ObjectPainter.h"
-#include "core/rendering/PaintInfo.h"
-#include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderMultiColumnFlowThread.h"
 
 namespace blink {
 
 RenderMultiColumnSet::RenderMultiColumnSet(RenderFlowThread* flowThread)
     : RenderRegion(0, flowThread)
     , m_columnHeight(0)
     , m_maxColumnHeight(RenderFlowThread::maxLogicalHeight())
     , m_minSpaceShortage(RenderFlowThread::maxLogicalHeight())
     , m_minimumColumnHeight(0)
@@ skipping 584 matching lines @@
 
 void RenderMultiColumnSet::detachRegion()
 {
     if (m_flowThread) {
         m_flowThread->removeRegionFromThread(this);
         m_flowThread = 0;
     }
 }
 
 }