Change LayoutState to be stack-allocated

Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 86 matching lines @@
 static RenderLayer::UpdateLayerPositionsFlags updateLayerPositionFlags(RenderLayer* layer, bool isRelayoutingSubtree, bool didFullPaintInvalidation)
 {
     RenderLayer::UpdateLayerPositionsFlags flags = didFullPaintInvalidation ? RenderLayer::NeedsFullRepaintInBacking : RenderLayer::CheckForRepaint;
 
     if (isRelayoutingSubtree && (layer->isPaginated() || layer->enclosingPaginationLayer()))
         flags |= RenderLayer::UpdatePagination;
 
     return flags;
 }
 
-class FrameViewLayoutStateMaintainer {
-    WTF_MAKE_NONCOPYABLE(FrameViewLayoutStateMaintainer);
-public:
-    FrameViewLayoutStateMaintainer(RenderObject& root, bool inSubtreeLayout)
-        : m_view(*root.view())
-        , m_inSubtreeLayout(inSubtreeLayout)
-        , m_disabled(inSubtreeLayout && m_view.shouldDisableLayoutStateForSubtree(root))
-    {
-        if (m_inSubtreeLayout)
-            m_view.pushLayoutState(root);
-        if (m_disabled)
-            m_view.disableLayoutState();
-    }
-
-    ~FrameViewLayoutStateMaintainer()
-    {
-        if (m_disabled)
-            m_view.enableLayoutState();
-        if (m_inSubtreeLayout)
-            m_view.popLayoutState();
-    }
-private:
-    RenderView& m_view;
-    bool m_inSubtreeLayout;
-    bool m_disabled;
-};
-
 FrameView::FrameView(LocalFrame* frame)
     : m_frame(frame)
     , m_canHaveScrollbars(true)
     , m_slowRepaintObjectCount(0)
     , m_hasPendingLayout(false)
     , m_layoutSubtreeRoot(0)
     , m_inSynchronousPostLayout(false)
     , m_postLayoutTasksTimer(this, &FrameView::postLayoutTimerFired)
     , m_updateWidgetsTimer(this, &FrameView::updateWidgetsTimerFired)
     , m_isTransparent(false)
@@ skipping 658 matching lines @@
 
     ASSERT(!isInPerformLayout());
     lifecycle().advanceTo(DocumentLifecycle::InPerformLayout);
 
     TemporaryChange<bool> changeInPerformLayout(m_inPerformLayout, true);
 
     // performLayout is the actual guts of layout().
     // FIXME: The 300 other lines in layout() probably belong in other helper functions
     // so that a single human could understand what layout() is actually doing.
 
-    FrameViewLayoutStateMaintainer statePusher(*rootForThisLayout, inSubtreeLayout);
+    LayoutState layoutState(*rootForThisLayout);
+
     forceLayoutParentViewIfNeeded();
 
     // FIXME (crbug.com/256657): Do not do two layouts for text autosizing.
     rootForThisLayout->layout();
     gatherDebugLayoutRects(rootForThisLayout);
 
     ResourceLoadPriorityOptimizer::resourceLoadPriorityOptimizer()->updateAllImageResourcePriorities();
 
     TextAutosizer* textAutosizer = frame().document()->textAutosizer();
     bool autosized;
@@ skipping 229 matching lines @@
     // We should only invalidate paints for the outer most layout. This works as
     // we continue to track paint invalidation rects until this function is called.
     ASSERT(!m_nestedLayoutCount);
 
     TRACE_EVENT1("blink", "FrameView::invalidateTree", "root", TRACE_STR_COPY(root->debugName().ascii().data()));
 
     // FIXME: really, we're in the paint invalidation phase here, and the compositing queries are legal.
     // Until those states are fully fledged, I'll just disable the ASSERTS.
     DisableCompositingQueryAsserts compositingQueryAssertsDisabler;
 
-    RootLayoutStateScope rootLayoutStateScope(*root);
+    LayoutState rootLayoutState(*root);
 
     root->invalidateTreeAfterLayout(*root->containerForPaintInvalidation());
 
     // Invalidate the paint of the frameviews scrollbars if needed
     if (hasVerticalBarDamage())
         invalidateRect(verticalBarDamage());
     if (hasHorizontalBarDamage())
         invalidateRect(horizontalBarDamage());
     resetScrollbarDamage();
 }
@@ skipping 2222 matching lines @@
 void FrameView::willRemoveScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::willRemoveScrollbar(scrollbar, orientation);
     if (AXObjectCache* cache = axObjectCache()) {
         cache->remove(scrollbar);
         cache->handleScrollbarUpdate(this);
     }
 }
 
 } // namespace WebCore