Add support for printing multicol containers, and enable it.

third_party/WebKit/Source/core/layout/LayoutView.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 22 matching lines @@
 #include "platform/heap/Handle.h"
 #include "platform/scroll/ScrollableArea.h"
 #include "wtf/OwnPtr.h"
 
 namespace blink {
 
 class FrameView;
 class PaintLayerCompositor;
 class LayoutQuote;
 class LayoutMedia;
+class ViewFragmentationContext;
 
 // LayoutView is the root of the layout tree and the Document's LayoutObject.
 //
 // It corresponds to the CSS concept of 'initial containing block' (or ICB).
 // http://www.w3.org/TR/CSS2/visudet.html#containing-block-details
 //
 // Its dimensions match that of the layout viewport. This viewport is used to
 // size elements, in particular fixed positioned elements.
 // LayoutView is always at position (0,0) relative to the document (and so isn't
 // necessarily in view).
@@ skipping 82 matching lines @@
     LayoutRect viewRect() const override;
     LayoutRect overflowClipRect(const LayoutPoint& location, OverlayScrollbarSizeRelevancy = IgnoreOverlayScrollbarSize) const override;
 
     bool shouldDoFullPaintInvalidationForNextLayout() const;
     bool doingFullPaintInvalidation() const;
 
     LayoutState* layoutState() const { return m_layoutState; }
 
     void updateHitTestResult(HitTestResult&, const LayoutPoint&) override;
 
+    ViewFragmentationContext* fragmentationContext() const { return m_fragmentationContext.get(); }
+
     LayoutUnit pageLogicalHeight() const { return m_pageLogicalHeight; }
     void setPageLogicalHeight(LayoutUnit height)
     {
         if (m_pageLogicalHeight != height) {
             m_pageLogicalHeight = height;
             m_pageLogicalHeightChanged = true;
         }
     }
     bool pageLogicalHeightChanged() const { return m_pageLogicalHeightChanged; }
 
@@ skipping 100 matching lines @@
     // Outside of printing, this is 0.
     LayoutUnit m_pageLogicalHeight;
     bool m_pageLogicalHeightChanged;
 
     // LayoutState is an optimization used during layout.
     // |m_layoutState| will be nullptr outside of layout.
     //
     // See the class comment for more details.
     LayoutState* m_layoutState;
 
+    OwnPtr<ViewFragmentationContext> m_fragmentationContext;
     OwnPtr<PaintLayerCompositor> m_compositor;
     RefPtr<IntervalArena> m_intervalArena;
 
     LayoutQuote* m_layoutQuoteHead;
     unsigned m_layoutCounterCount;
 
     unsigned m_hitTestCount;
     unsigned m_hitTestCacheHits;
     OwnPtrWillBePersistent<HitTestCache> m_hitTestCache;
 
@@ skipping 24 matching lines @@
             m_paintInvalidationState->m_cachedOffsetsEnabled = true;
     }
 private:
     const PaintInvalidationState* m_paintInvalidationState;
     bool m_didDisable;
 };
 
 } // namespace blink
 
 #endif // LayoutView_h