Issue repaints before and after changing the squashing assignment of a RenderLayer.

Source/core/rendering/RenderLayerRepainter.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 134 matching lines @@
 }
 
 // Since we're only painting non-composited layers, we know that they all share the same repaintContainer.
 void RenderLayerRepainter::repaintIncludingNonCompositingDescendants()
 {
     repaintIncludingNonCompositingDescendantsInternal(m_renderer.containerForRepaint());
 }
 
 void RenderLayerRepainter::repaintIncludingNonCompositingDescendantsInternal(const RenderLayerModelObject* repaintContainer)
 {
-    m_renderer.repaintUsingContainer(repaintContainer, pixelSnappedIntRect(m_renderer.computeRepaintRect()), InvalidationLayer);
+    m_renderer.repaintUsingContainer(repaintContainer, pixelSnappedIntRect(m_renderer.boundsRectForRepaint(repaintContainer)), InvalidationLayer);
+
+    // FIXME: Repaints can be issued during style recalc at present, via RenderLayerModelObject::styleWillChange. This happens in scenarios when
+    // repaint is needed but not layout.
+    DisableCompositingQueryAsserts disabler;
 
     for (RenderLayer* curr = m_renderer.layer()->firstChild(); curr; curr = curr->nextSibling()) {
-        if (!curr->hasCompositedLayerMapping())
+        if (curr->compositingState() != PaintsIntoOwnBacking && curr->compositingState() != PaintsIntoGroupedBacking)
             curr->repainter().repaintIncludingNonCompositingDescendantsInternal(repaintContainer);
     }
 }
 
 LayoutRect RenderLayerRepainter::repaintRectIncludingNonCompositingDescendants() const
 {
     LayoutRect repaintRect;
     if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
         repaintRect = m_renderer.previousPaintInvalidationRect();
     else
         repaintRect = m_repaintRect;
 
     for (RenderLayer* child = m_renderer.layer()->firstChild(); child; child = child->nextSibling()) {
         // Don't include repaint rects for composited child layers; they will paint themselves and have a different origin.
-        if (child->hasCompositedLayerMapping())
+        if (child->compositingState() == PaintsIntoOwnBacking || child->compositingState() == PaintsIntoGroupedBacking)
             continue;
 
         repaintRect.unite(child->repainter().repaintRectIncludingNonCompositingDescendants());
     }
     return repaintRect;
 }
 
 void RenderLayerRepainter::setBackingNeedsRepaint()
 {
     // There is only one call site, and that call site ensures that the compositing state is PaintsIntoOwnBacking.
@@ skipping 74 matching lines @@
 RenderLayer* RenderLayerRepainter::enclosingFilterRepaintLayer() const
 {
     for (const RenderLayer* curr = m_renderer.layer(); curr; curr = curr->parent()) {
         if ((curr != m_renderer.layer() && curr->requiresFullLayerImageForFilters()) || curr->compositingState() == PaintsIntoOwnBacking || curr->isRootLayer())
             return const_cast<RenderLayer*>(curr);
     }
     return 0;
 }
 
 } // Namespace WebCore