Remove negative z-index.

sky/engine/core/rendering/RenderLayer.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 287 matching lines @@
 // Return true if this layer or any preserve-3d descendants have 3d.
 bool RenderLayer::update3DTransformedDescendantStatus()
 {
     if (m_3DTransformedDescendantStatusDirty) {
         m_has3DTransformedDescendant = false;
 
         m_stackingNode->updateZOrderLists();
 
         // Transformed or preserve-3d descendants can only be in the z-order lists, not
         // in the normal flow list, so we only need to check those.
-        RenderLayerStackingNodeIterator iterator(*m_stackingNode.get(), PositiveZOrderChildren | NegativeZOrderChildren);
+        RenderLayerStackingNodeIterator iterator(*m_stackingNode.get(), PositiveZOrderChildren);
         while (RenderLayerStackingNode* node = iterator.next())
             m_has3DTransformedDescendant |= node->layer()->update3DTransformedDescendantStatus();
 
         m_3DTransformedDescendantStatusDirty = false;
     }
 
     // If we live in a 3d hierarchy, then the layer at the root of that hierarchy needs
     // the m_has3DTransformedDescendant set.
     if (preserves3D())
         return has3DTransform() || m_has3DTransformedDescendant;
@@ skipping 717 matching lines @@
     // If this layer's renderer is a child of the paintingRoot, we render unconditionally, which
     // is done by passing a nil paintingRoot down to our renderer (as if no paintingRoot was ever set).
     // Else, our renderer tree may or may not contain the painting root, so we pass that root along
     // so it will be tested against as we descend through the renderers.
     RenderObject* paintingRootForRenderer = 0;
     if (localPaintingInfo.paintingRoot && !renderer()->isDescendantOf(localPaintingInfo.paintingRoot))
         paintingRootForRenderer = localPaintingInfo.paintingRoot;
 
     LayoutPoint layerLocation = toPoint(layerBounds.location() - renderBoxLocation() + localPaintingInfo.subPixelAccumulation);
 
-    paintChildren(NegativeZOrderChildren, context, paintingInfo, paintFlags);
-
     if (shouldPaintContent) {
         paintForeground(context, transparencyLayerContext, paintingInfo.paintDirtyRect, haveTransparency,
             localPaintingInfo, paintingRootForRenderer, layerLocation, foregroundRect);
     }
 
     paintOutline(context, localPaintingInfo, paintingRootForRenderer, layerLocation, outlineRect);
     paintChildren(NormalFlowChildren | PositiveZOrderChildren, context, paintingInfo, paintFlags);
 
     if (isPaintingOverlayScrollbars)
         paintOverflowControls(context, localPaintingInfo, layerLocation, backgroundRect);
@@ skipping 376 matching lines @@
                 result = tempResult;
             if (!depthSortDescendants)
                 return this;
             // Foreground can depth-sort with descendant layers, so keep this as a candidate.
             candidateLayer = this;
         } else if (result.isRectBasedTest()) {
             result.append(tempResult);
         }
     }
 
-    // Now check our negative z-index children.
-    hitLayer = hitTestChildren(NegativeZOrderChildren, rootLayer, request, result, hitTestRect, hitTestLocation,
-        localTransformState.get(), zOffsetForDescendantsPtr, zOffset, unflattenedTransformState.get(), depthSortDescendants);
-    if (hitLayer) {
-        if (!depthSortDescendants)
-            return hitLayer;
-        candidateLayer = hitLayer;
-    }
-
     // If we found a layer, return. Child layers, and foreground always render in front of background.
     if (candidateLayer)
         return candidateLayer;
 
     if (isSelfPaintingLayer() && backgroundRect.intersects(hitTestLocation)) {
         HitTestResult tempResult(result.hitTestLocation());
         if (hitTestContents(request, tempResult, layerBounds, hitTestLocation, HitTestSelf)
             && isHitCandidate(this, false, zOffsetForContentsPtr, unflattenedTransformState.get())) {
             if (result.isRectBasedTest())
                 result.append(tempResult);
@@ skipping 395 matching lines @@
     }
 }
 
 void showLayerTree(const blink::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif