Store repaint rects in the coordinate space of their backing GraphicsLayer.

Source/core/rendering/RenderBox.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 1564 matching lines @@
     if (!shouldCheckForInvalidationAfterLayout())
         return;
 
     bool establishesNewRepaintContainer = isRepaintContainer();
     const RenderLayerModelObject& newRepaintContainer = *adjustCompositedContainerForSpecialAncestors(establishesNewRepaintContainer ? this : &repaintContainer);
     // FIXME: This assert should be re-enabled when we move repaint to after compositing update. crbug.com/360286
     // ASSERT(&newRepaintContainer == containerForRepaint());
 
     const LayoutRect oldRepaintRect = previousRepaintRect();
     const LayoutPoint oldPositionFromRepaintContainer = previousPositionFromRepaintContainer();
-    setPreviousRepaintRect(clippedOverflowRectForRepaint(&newRepaintContainer));
+    setPreviousRepaintRect(boundsRectForRepaint(&newRepaintContainer));
     setPreviousPositionFromRepaintContainer(positionFromRepaintContainer(&newRepaintContainer));
 
     // If we are set to do a full repaint that means the RenderView will be
     // invalidated. We can then skip issuing of invalidations for the child
     // renderers as they'll be covered by the RenderView.
     if (view()->doingFullRepaint() && this != view()) {
         LayoutStateMaintainer statePusher(*this, isTableRow() ? LayoutSize() : locationOffset());
         RenderObject::repaintTreeAfterLayout(newRepaintContainer);
         return;
     }
@@ skipping 408 matching lines @@
 
     LayoutRect r = visualOverflowRect();
 
     RenderView* v = view();
     if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled() && v) {
         // FIXME: layoutDelta needs to be applied in parts before/after transforms and
         // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
         r.move(v->layoutDelta());
     }
 
-    computeRectForRepaint(repaintContainer, r);
+    adjustRectToRepaintBackingCoords(repaintContainer, r);
     return r;
 }
 
-void RenderBox::computeRectForRepaint(const RenderLayerModelObject* repaintContainer, LayoutRect& rect, bool fixed) const
+void RenderBox::adjustRectToRepaintBackingCoords(const RenderLayerModelObject* repaintContainer, LayoutRect& rect, bool fixed) const
 {
     // The rect we compute at each step is shifted by our x/y offset in the parent container's coordinate space.
     // Only when we cross a writing mode boundary will we have to possibly flipForWritingMode (to convert into a more appropriate
     // offset corner for the enclosing container).  This allows for a fully RL or BT document to repaint
     // properly even during layout, since the rect remains flipped all the way until the end.
     //
     // RenderView::computeRectForRepaint then converts the rect to physical coordinates.  We also convert to
     // physical when we hit a repaintContainer boundary.  Therefore the final rect returned is always in the
     // physical coordinate space of the repaintContainer.
     RenderStyle* styleToUse = style();
@@ skipping 76 matching lines @@
             return;
     }
 
     if (containerSkipped) {
         // If the repaintContainer is below o, then we need to map the rect into repaintContainer's coordinates.
         LayoutSize containerOffset = repaintContainer->offsetFromAncestorContainer(o);
         rect.move(-containerOffset);
         return;
     }
 
-    o->computeRectForRepaint(repaintContainer, rect, fixed);
+    o->adjustRectToRepaintBackingCoords(repaintContainer, rect, fixed);
 }
 
 void RenderBox::repaintDuringLayoutIfMoved(const LayoutRect& oldRect)
 {
     if (oldRect.location() != m_frameRect.location()) {
         LayoutRect newRect = m_frameRect;
         // The child moved.  Invalidate the object's old and new positions.  We have to do this
         // since the object may not have gotten a layout.
         m_frameRect = oldRect;
         repaint();
@@ skipping 2562 matching lines @@
         return 0;
 
     if (!layoutState && !flowThreadContainingBlock())
         return 0;
 
     RenderBlock* containerBlock = containingBlock();
     return containerBlock->offsetFromLogicalTopOfFirstPage() + logicalTop();
 }
 
 } // namespace WebCore