*** DO NOT LAND *** Measure the size and complexity of the old multicol implementation.

Source/core/rendering/RenderLayer.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. 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>
@@ skipping 153 matching lines @@
         UpdatePagination = 1 << 4
     };
     typedef unsigned UpdateLayerPositionsFlags;
     static const UpdateLayerPositionsFlags defaultFlags = CheckForRepaint | IsCompositingUpdateRoot | UpdateCompositingLayers;
 
     void updateLayerPositionsAfterLayout(const RenderLayer* rootLayer, UpdateLayerPositionsFlags);
 
     void updateLayerPositionsAfterOverflowScroll();
     void updateLayerPositionsAfterDocumentScroll();
 
-    bool isPaginated() const { return m_isPaginated; }
     RenderLayer* enclosingPaginationLayer() const { return m_enclosingPaginationLayer; }
 
     void updateTransform();
 
     const LayoutSize& offsetForInFlowPosition() const { return m_offsetForInFlowPosition; }
 
     void addBlockSelectionGapsBounds(const LayoutRect&);
     void clearBlockSelectionGapsBounds();
     void repaintBlockSelectionGaps();
     bool hasBlockSelectionGapBounds() const;
@@ skipping 54 matching lines @@
     // Ancestor scrolling layer at or above our containing block.
     RenderLayer* ancestorScrollingLayer() const;
 
     RenderLayer* enclosingFilterLayer(IncludeSelfOrNot = IncludeSelf) const;
     RenderLayer* enclosingFilterRepaintLayer() const;
     bool hasAncestorWithFilterOutsets() const;
 
     bool canUseConvertToLayerCoords() const
     {
         // These RenderObjects have an impact on their layers without the renderers knowing about it.
-        return !renderer()->hasColumns() && !renderer()->hasTransform() && !renderer()->isSVGRoot();
+        return !renderer()->hasTransform() && !renderer()->isSVGRoot();
     }
 
     void convertToPixelSnappedLayerCoords(const RenderLayer* ancestorLayer, IntPoint& location) const;
     void convertToPixelSnappedLayerCoords(const RenderLayer* ancestorLayer, IntRect&) const;
     void convertToLayerCoords(const RenderLayer* ancestorLayer, LayoutPoint& location) const;
     void convertToLayerCoords(const RenderLayer* ancestorLayer, LayoutRect&) const;
 
     // The two main functions that use the layer system.  The paint method
     // paints the layers that intersect the damage rect from back to
     // front.  The hitTest method looks for mouse events by walking
@@ skipping 226 matching lines @@
     void setParent(RenderLayer* parent);
     void setFirstChild(RenderLayer* first) { m_first = first; }
     void setLastChild(RenderLayer* last) { m_last = last; }
 
     LayoutPoint renderBoxLocation() const { return renderer()->isBox() ? toRenderBox(renderer())->location() : LayoutPoint(); }
 
     void paintLayerContentsAndReflection(GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags);
     void paintLayerByApplyingTransform(GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags, const LayoutPoint& translationOffset = LayoutPoint());
     void paintLayerContents(GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags);
     void paintChildren(unsigned childrenToVisit, GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags);
-    void paintPaginatedChildLayer(RenderLayer* childLayer, GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags);
-    void paintChildLayerIntoColumns(RenderLayer* childLayer, GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags, const Vector<RenderLayer*>& columnLayers, size_t columnIndex);
 
     void collectFragments(LayerFragments&, const RenderLayer* rootLayer, RenderRegion*, const LayoutRect& dirtyRect,
         ClipRectsType, OverlayScrollbarSizeRelevancy inOverlayScrollbarSizeRelevancy = IgnoreOverlayScrollbarSize,
         ShouldRespectOverflowClip = RespectOverflowClip, const LayoutPoint* offsetFromRoot = 0,
         const LayoutSize& subPixelAccumulation = LayoutSize(), const LayoutRect* layerBoundingBox = 0);
     void updatePaintingInfoForFragments(LayerFragments&, const LayerPaintingInfo&, PaintLayerFlags, bool shouldPaintContent, const LayoutPoint* offsetFromRoot);
     void paintBackgroundForFragments(const LayerFragments&, GraphicsContext*, GraphicsContext* transparencyLayerContext,
         const LayoutRect& transparencyPaintDirtyRect, bool haveTransparency, const LayerPaintingInfo&, PaintBehavior, RenderObject* paintingRootForRenderer);
     void paintForegroundForFragments(const LayerFragments&, GraphicsContext*, GraphicsContext* transparencyLayerContext,
         const LayoutRect& transparencyPaintDirtyRect, bool haveTransparency, const LayerPaintingInfo&, PaintBehavior, RenderObject* paintingRootForRenderer,
         bool selectionOnly, bool forceBlackText);
     void paintForegroundForFragmentsWithPhase(PaintPhase, const LayerFragments&, GraphicsContext*, const LayerPaintingInfo&, PaintBehavior, RenderObject* paintingRootForRenderer);
     void paintOutlineForFragments(const LayerFragments&, GraphicsContext*, const LayerPaintingInfo&, PaintBehavior, RenderObject* paintingRootForRenderer);
     void paintOverflowControlsForFragments(const LayerFragments&, GraphicsContext*, const LayerPaintingInfo&);
     void paintMaskForFragments(const LayerFragments&, GraphicsContext*, const LayerPaintingInfo&, RenderObject* paintingRootForRenderer);
     void paintChildClippingMaskForFragments(const LayerFragments&, GraphicsContext*, const LayerPaintingInfo&, RenderObject* paintingRootForRenderer);
     void paintTransformedLayerIntoFragments(GraphicsContext*, const LayerPaintingInfo&, PaintLayerFlags);
 
     RenderLayer* hitTestLayer(RenderLayer* rootLayer, RenderLayer* containerLayer, const HitTestRequest& request, HitTestResult& result,
                               const LayoutRect& hitTestRect, const HitTestLocation&, bool appliedTransform,
                               const HitTestingTransformState* transformState = 0, double* zOffset = 0);
     RenderLayer* hitTestLayerByApplyingTransform(RenderLayer* rootLayer, RenderLayer* containerLayer, const HitTestRequest&, HitTestResult&,
         const LayoutRect& hitTestRect, const HitTestLocation&, const HitTestingTransformState* = 0, double* zOffset = 0,
         const LayoutPoint& translationOffset = LayoutPoint());
     RenderLayer* hitTestChildren(ChildrenIteration, RenderLayer* rootLayer, const HitTestRequest&, HitTestResult&,
                              const LayoutRect& hitTestRect, const HitTestLocation&,
                              const HitTestingTransformState* transformState, double* zOffsetForDescendants, double* zOffset,
                              const HitTestingTransformState* unflattenedTransformState, bool depthSortDescendants);
-    RenderLayer* hitTestPaginatedChildLayer(RenderLayer* childLayer, RenderLayer* rootLayer, const HitTestRequest& request, HitTestResult& result,
-                                            const LayoutRect& hitTestRect, const HitTestLocation&,
-                                            const HitTestingTransformState* transformState, double* zOffset);
-    RenderLayer* hitTestChildLayerColumns(RenderLayer* childLayer, RenderLayer* rootLayer, const HitTestRequest& request, HitTestResult& result,
-                                          const LayoutRect& hitTestRect, const HitTestLocation&,
-                                          const HitTestingTransformState* transformState, double* zOffset,
-                                          const Vector<RenderLayer*>& columnLayers, size_t columnIndex);
 
     PassRefPtr<HitTestingTransformState> createLocalTransformState(RenderLayer* rootLayer, RenderLayer* containerLayer,
                             const LayoutRect& hitTestRect, const HitTestLocation&,
                             const HitTestingTransformState* containerTransformState,
                             const LayoutPoint& translationOffset = LayoutPoint()) const;
 
     bool hitTestContents(const HitTestRequest&, HitTestResult&, const LayoutRect& layerBounds, const HitTestLocation&, HitTestFilter) const;
     bool hitTestContentsForFragments(const LayerFragments&, const HitTestRequest&, HitTestResult&, const HitTestLocation&, HitTestFilter, bool& insideClipRect) const;
     RenderLayer* hitTestTransformedLayerInFragments(RenderLayer* rootLayer, RenderLayer* containerLayer, const HitTestRequest&, HitTestResult&,
         const LayoutRect& hitTestRect, const HitTestLocation&, const HitTestingTransformState* = 0, double* zOffset = 0);
@@ skipping 83 matching lines @@
                                  // we ended up painting this layer or any descendants (and therefore need to
                                  // blend).
 
     unsigned m_visibleContentStatusDirty : 1;
     unsigned m_hasVisibleContent : 1;
     unsigned m_visibleDescendantStatusDirty : 1;
     unsigned m_hasVisibleDescendant : 1;
 
     unsigned m_hasVisibleNonLayerContent : 1;
 
-    unsigned m_isPaginated : 1; // If we think this layer is split by a multi-column ancestor, then this bit will be set.
-
     unsigned m_3DTransformedDescendantStatusDirty : 1;
     // Set on a stacking context layer that has 3D descendants anywhere
     // in a preserves3D hierarchy. Hint to do 3D-aware hit testing.
     unsigned m_has3DTransformedDescendant : 1;
 
     unsigned m_containsDirtyOverlayScrollbars : 1;
 
     // This is an optimization added for <table>.
     // Currently cells do not need to update their repaint rectangles when scrolling. This also
     // saves a lot of time when scrolling on a table.
@@ skipping 82 matching lines @@
 
 } // namespace WebCore
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showLayerTree(const WebCore::RenderLayer*);
 void showLayerTree(const WebCore::RenderObject*);
 #endif
 
 #endif // RenderLayer_h