Improve handling of PaintInvalidationLayer (renamed to PaintInvalidationSubtree)

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. 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
@@ skipping 3856 matching lines @@
 {
     if (PaintLayerScrollableArea* scrollableArea = this->getScrollableArea()) {
         if (scrollableArea->hasHorizontalScrollbar() && !scrollableArea->layerForHorizontalScrollbar())
             return true;
         if (scrollableArea->hasVerticalScrollbar() && !scrollableArea->layerForVerticalScrollbar())
             return true;
     }
     return false;
 }
 
-PaintInvalidationReason LayoutBox::getPaintInvalidationReason(const LayoutBoxModelObject& paintInvalidationContainer,
+PaintInvalidationReason LayoutBox::getPaintInvalidationReason(const PaintInvalidationState& paintInvalidationState,
     const LayoutRect& oldBounds, const LayoutPoint& oldLocation, const LayoutRect& newBounds, const LayoutPoint& newLocation) const
 {
-    PaintInvalidationReason invalidationReason = LayoutBoxModelObject::getPaintInvalidationReason(paintInvalidationContainer, oldBounds, oldLocation, newBounds, newLocation);
+    PaintInvalidationReason invalidationReason = LayoutBoxModelObject::getPaintInvalidationReason(paintInvalidationState, oldBounds, oldLocation, newBounds, newLocation);
     if (isFullPaintInvalidationReason(invalidationReason))
         return invalidationReason;
 
     if (isLayoutView()) {
         const LayoutView* layoutView = toLayoutView(this);
         // In normal compositing mode, root background doesn't need to be invalidated for
         // box changes, because the background always covers the whole document rect
         // and clipping is done by compositor()->m_containerLayer. Also the scrollbars
         // are always composited. There are no other box decoration on the LayoutView thus
         // we can safely exit here.
         if (layoutView->usesCompositing() && (!document().settings() || !document().settings()->rootLayerScrolls()))
             return invalidationReason;
     }
 
     // If the transform is not identity or translation, incremental invalidation is not applicable
     // because the difference between oldBounds and newBounds doesn't cover all area needing invalidation.
     // FIXME: Should also consider ancestor transforms since paintInvalidationContainer. crbug.com/426111.
     if (invalidationReason == PaintInvalidationIncremental
-        && paintInvalidationContainer != this
+        && paintInvalidationState.paintInvalidationContainer() != this
         && hasLayer() && layer()->transform() && !layer()->transform()->isIdentityOrTranslation())
         return PaintInvalidationBoundsChange;
 
     if (style()->backgroundLayers().thisOrNextLayersUseContentBox() || style()->maskLayers().thisOrNextLayersUseContentBox() || style()->boxSizing() == BoxSizingBorderBox) {
         LayoutRect oldContentBoxRect = m_rareData ? m_rareData->m_previousContentBoxRect : LayoutRect();
         LayoutRect newContentBoxRect = contentBoxRect();
         if (oldContentBoxRect != newContentBoxRect)
             return PaintInvalidationContentBoxChange;
     }
 
@@ skipping 940 matching lines @@
     if (!flowThread) {
         // If there's no flow thread, we're not nested. All pages have the same height. Give up.
         return strutToNextPage;
     }
     // Start searching for a suitable offset at the top of the next page or column.
     LayoutUnit flowThreadOffset = offsetFromLogicalTopOfFirstPage() + nextPageLogicalTop;
     return strutToNextPage + flowThread->nextLogicalTopForUnbreakableContent(flowThreadOffset, contentLogicalHeight) - flowThreadOffset;
 }
 
 } // namespace blink