Change LayoutState to be stack-allocated

Source/core/rendering/RenderBlock.cpp

 /*
  * 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, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
@@ skipping 359 matching lines @@
     // Note, we don't want to early out here using shouldCheckForInvalidationAfterLayout as
     // we have to make sure we go through any positioned objects as they won't be seen in
     // the normal tree walk.
 
     if (shouldCheckForPaintInvalidationAfterLayout())
         RenderBox::invalidateTreeAfterLayout(invalidationContainer);
 
     // Take care of positioned objects. This is required as LayoutState keeps a single clip rect.
     if (TrackedRendererListHashSet* positionedObjects = this->positionedObjects()) {
         TrackedRendererListHashSet::iterator end = positionedObjects->end();
-        LayoutStateMaintainer statePusher(*this, isTableRow() ? LayoutSize() : locationOffset());
+        LayoutState state(*this, isTableRow() ? LayoutSize() : locationOffset());
         for (TrackedRendererListHashSet::iterator it = positionedObjects->begin(); it != end; ++it) {
             RenderBox* box = *it;
 
             // One of the renderers we're skipping over here may be the child's repaint container,
             // so we can't pass our own repaint container along.
             const RenderLayerModelObject& repaintContainerForChild = *box->containerForPaintInvalidation();
 
             // If the positioned renderer is absolutely positioned and it is inside
             // a relatively positioend inline element, we need to account for
             // the inline elements position in LayoutState.
@@ skipping 1175 matching lines @@
     // Check if we need to do a full layout.
     if (normalChildNeedsLayout() || selfNeedsLayout())
         return false;
 
     // Check that we actually need to do a simplified layout.
     if (!posChildNeedsLayout() && !(needsSimplifiedNormalFlowLayout() || needsPositionedMovementLayout()))
         return false;
 
 
     {
-        // LayoutStateMaintainer needs this deliberate scope to pop before repaint
-        LayoutStateMaintainer statePusher(*this, locationOffset());
+        // LayoutState needs this deliberate scope to pop before repaint
+        LayoutState state(*this, locationOffset());
 
         if (needsPositionedMovementLayout() && !tryLayoutDoingPositionedMovementOnly())
             return false;
 
         FastTextAutosizer::LayoutScope fastTextAutosizerLayoutScope(this);
 
         // Lay out positioned descendants or objects that just need to recompute overflow.
         if (needsSimplifiedNormalFlowLayout())
             simplifiedNormalFlowLayout();
 
@@ skipping 3449 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore