[New Multicolumn] Layout support for column-span:all.

Source/core/rendering/RenderLayer.cpp

Index: Source/core/rendering/RenderLayer.cpp
diff --git a/Source/core/rendering/RenderLayer.cpp b/Source/core/rendering/RenderLayer.cpp
index a695829e1b19abbd4aea11f4f8f83fd1b9f2cf2e..13fa3e35821ad5ea00569205e2da4ce6f18fe624 100644
--- a/Source/core/rendering/RenderLayer.cpp
+++ b/Source/core/rendering/RenderLayer.cpp
@@ -807,7 +807,7 @@ LayoutPoint RenderLayer::location() const
         localPoint.moveBy(box->topLeftLocation());
     }
 
-    if (!renderer()->isOutOfFlowPositioned() && renderer()->parent()) {
+    if (!renderer()->isOutOfFlowPositioned() && !renderer()->isColumnSpanAll() && renderer()->parent()) {
         // We must adjust our position by walking up the render tree looking for the
         // nearest enclosing object with a layer.
         RenderObject* curr = renderer()->parent();
@@ -1397,8 +1397,14 @@ static inline const RenderLayer* accumulateOffsetTowardsAncestor(const RenderLay
             location += (thisCoords - ancestorCoords);
             return ancestorLayer;
         }
-    } else
+    } else if (renderer->isColumnSpanAll()) {
+        RenderBlock* multicolContainer = renderer->containingBlock();
+        ASSERT(toRenderBlockFlow(multicolContainer)->multiColumnFlowThread());
+        parentLayer = multicolContainer->layer();
+        ASSERT(parentLayer);
+    } else {
         parentLayer = layer->parent();
+    }
 
     if (!parentLayer)
         return 0;