[New Multicolumn] Stay out of the old multicol machinery for column-span:all.

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
  * License as published by the Free Software Foundation; either
@@ skipping 771 matching lines @@
             ASSERT(beforeChild->parent() == this);
             if (beforeChild->parent() != this) {
                 // We should never reach here. If we do, we need to use the
                 // safe fallback to use the topmost beforeChild container.
                 beforeChild = beforeChildContainer;
             }
         }
     }
 
     // Check for a spanning element in columns.
-    if (gColumnFlowSplitEnabled) {
+    if (gColumnFlowSplitEnabled && !document().regionBasedColumnsEnabled()) {
         RenderBlockFlow* columnsBlockAncestor = columnsBlockForSpanningElement(newChild);
         if (columnsBlockAncestor) {
             TemporaryChange<bool> columnFlowSplitEnabled(gColumnFlowSplitEnabled, false);
             // We are placing a column-span element inside a block.
             RenderBlockFlow* newBox = createAnonymousColumnSpanBlock();
 
             if (columnsBlockAncestor != this && !isRenderFlowThread()) {
                 // We are nested inside a multi-column element and are being split by the span. We have to break up
                 // our block into continuations.
                 RenderBoxModelObject* oldContinuation = continuation();
@@ skipping 4104 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore