Eliminate unnecessary includes and pointless forward declarations in LayoutBlock.h

third_party/WebKit/Source/core/layout/LayoutBlock.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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.
  */
 
 #ifndef LayoutBlock_h
 #define LayoutBlock_h
 
 #include "core/CoreExport.h"
-#include "core/layout/FloatingObjects.h"
-#include "core/layout/GapRects.h"
 #include "core/layout/LayoutBox.h"
-#include "core/style/ShapeValue.h"
-#include "platform/text/TextBreakIterator.h"
 #include "wtf/ListHashSet.h"
 #include "wtf/OwnPtr.h"
 
 namespace blink {
 
 struct PaintInfo;
+class LineLayoutBox;
 class WordMeasurement;
 
 typedef WTF::ListHashSet<LayoutBox*, 16> TrackedLayoutBoxListHashSet;
 typedef WTF::HashMap<const LayoutBlock*, OwnPtr<TrackedLayoutBoxListHashSet>> TrackedDescendantsMap;
 typedef WTF::HashMap<const LayoutBox*, LayoutBlock*> TrackedContainerMap;
 typedef Vector<WordMeasurement, 64> WordMeasurements;
 
 enum ContainingBlockState { NewContainingBlock, SameContainingBlock };
 
 // LayoutBlock is the class that is used by any LayoutObject
@@ skipping 392 matching lines @@
     // FIXME: This is temporary as we move code that accesses block flow
     // member variables out of LayoutBlock and into LayoutBlockFlow.
     friend class LayoutBlockFlow;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlock, isLayoutBlock());
 
 } // namespace blink
 
 #endif // LayoutBlock_h