C++11: Replace 0 with nullptr where applicable in layout code.

Source/core/layout/LayoutState.cpp

 /*
  * Copyright (C) 2007 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
@@ skipping 18 matching lines @@
 #include "core/layout/LayoutFlowThread.h"
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutView.h"
 
 namespace blink {
 
 LayoutState::LayoutState(LayoutUnit pageLogicalHeight, bool pageLogicalHeightChanged, LayoutView& view)
     : m_isPaginated(pageLogicalHeight)
     , m_pageLogicalHeightChanged(pageLogicalHeightChanged)
     , m_containingBlockLogicalWidthChanged(false)
-    , m_flowThread(0)
-    , m_next(0)
+    , m_flowThread(nullptr)
+    , m_next(nullptr)
     , m_pageLogicalHeight(pageLogicalHeight)
     , m_layoutObject(view)
 {
     ASSERT(!view.layoutState());
     view.pushLayoutState(*this);
 }
 
 LayoutState::LayoutState(LayoutBox& layoutObject, const LayoutSize& offset, LayoutUnit pageLogicalHeight, bool pageLogicalHeightChanged, bool containingBlockLogicalWidthChanged)
     : m_containingBlockLogicalWidthChanged(containingBlockLogicalWidthChanged)
     , m_next(layoutObject.view()->layoutState())
@@ skipping 51 matching lines @@
         }
     }
 
     // FIXME: <http://bugs.webkit.org/show_bug.cgi?id=13443> Apply control clip if present.
 }
 
 LayoutState::LayoutState(LayoutObject& root)
     : m_isPaginated(false)
     , m_pageLogicalHeightChanged(false)
     , m_containingBlockLogicalWidthChanged(false)
-    , m_flowThread(0)
+    , m_flowThread(nullptr)
     , m_next(root.view()->layoutState())
     , m_pageLogicalHeight(0)
     , m_layoutObject(root)
 {
     ASSERT(!m_next);
     // We'll end up pushing in LayoutView itself, so don't bother adding it.
     if (root.isLayoutView())
         return;
 
     root.view()->pushLayoutState(*this);
@@ skipping 18 matching lines @@
 }
 
 LayoutUnit LayoutState::pageLogicalOffset(const LayoutBox& child, const LayoutUnit& childLogicalOffset) const
 {
     if (child.isHorizontalWritingMode())
         return m_layoutOffset.height() + childLogicalOffset - m_pageOffset.height();
     return m_layoutOffset.width() + childLogicalOffset - m_pageOffset.width();
 }
 
 } // namespace blink