[New Multicolumn] Actual support for layout of column-span:all.

Source/core/rendering/RenderMultiColumnSpannerSet.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef RenderMultiColumnSpannerSet_h
 #define RenderMultiColumnSpannerSet_h
 
 #include "core/rendering/RenderMultiColumnSet.h"
 
 namespace blink {
@@ skipping 10 matching lines @@
 class RenderMultiColumnSpannerSet final : public RenderMultiColumnSet {
 public:
     virtual bool isOfType(RenderObjectType type) const override { return type == RenderObjectRenderMultiColumnSpannerSet || RenderMultiColumnSet::isOfType(type); }
 
     static RenderMultiColumnSpannerSet* createAnonymous(RenderMultiColumnFlowThread*, RenderStyle* parentStyle, RenderBox*);
 
     RenderBox* rendererInFlowThread() const { return m_rendererInFlowThread; }
 
 protected:
     virtual bool recalculateColumnHeight(BalancedHeightCalculation) override;
+    virtual void computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit logicalTop, LogicalExtentComputedValues&) const override;
+    virtual LayoutUnit pageLogicalHeight() const override;
     virtual const char* renderName() const override;
 
 private:
     RenderMultiColumnSpannerSet(RenderMultiColumnFlowThread*, RenderBox*);
 
     RenderBox* m_rendererInFlowThread; // The actual column-span:all renderer inside the flow thread.
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderMultiColumnSpannerSet, isRenderMultiColumnSpannerSet());
 
 } // namespace blink
 
 #endif