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

Source/core/rendering/RenderFlowThread.cpp

 /*
  * Copyright (C) 2011 Adobe Systems Incorporated. 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.
@@ skipping 13 matching lines @@
  * 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/RenderFlowThread.h"
 
-#include "core/dom/Node.h"
 #include "core/rendering/FlowThreadController.h"
-#include "core/rendering/HitTestRequest.h"
-#include "core/rendering/HitTestResult.h"
 #include "core/rendering/PaintInfo.h"
-#include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderMultiColumnSet.h"
 #include "core/rendering/RenderView.h"
-#include "platform/PODIntervalTree.h"
-#include "platform/geometry/TransformState.h"
 
 namespace blink {
 
 RenderFlowThread::RenderFlowThread()
     : RenderBlockFlow(0)
     , m_regionsInvalidated(false)
     , m_regionsHaveUniformLogicalHeight(true)
     , m_pageLogicalSizeChanged(false)
 {
     setFlowThreadState(InsideOutOfFlowThread);
@@ skipping 338 matching lines @@
 {
     if (!m_renderFlowThread)
         return;
     RenderView* view = m_renderFlowThread->view();
     ASSERT(view->flowThreadController()->currentRenderFlowThread() == m_renderFlowThread);
     view->flowThreadController()->setCurrentRenderFlowThread(m_previousRenderFlowThread);
 }
 
 
 } // namespace blink