Remove the old multicol implementation.

Source/core/layout/LayoutBoxModelObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. 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
@@ skipping 834 matching lines @@
     if (o->isLayoutFlowThread()) {
         // Descending into a flow thread. Convert to the local coordinate space, i.e. flow thread coordinates.
         const LayoutFlowThread* flowThread = toLayoutFlowThread(o);
         LayoutPoint visualPoint = LayoutPoint(transformState.mappedPoint());
         transformState.move(visualPoint - flowThread->visualPointToFlowThreadPoint(visualPoint));
         // |containerOffset| is also in visual coordinates. Convert to flow thread coordinates.
         // TODO(mstensho): Wouldn't it be better add a parameter to instruct offsetFromContainer()
         // to return flowthread coordinates in the first place? We're effectively performing two
         // conversions here, when in fact none is needed.
         containerOffset = toLayoutSize(flowThread->visualPointToFlowThreadPoint(toLayoutPoint(containerOffset)));
-    } else if (!style()->hasOutOfFlowPosition() && o->hasColumns()) {
-        LayoutBlock* block = toLayoutBlock(o);
-        LayoutPoint point(roundedLayoutPoint(transformState.mappedPoint()));
-        point -= containerOffset;
-        block->adjustForColumnRect(containerOffset, point);
     }
 
     bool preserve3D = mode & UseTransforms && (o->style()->preserves3D() || style()->preserves3D());
     if (mode & UseTransforms && shouldUseTransformFromContainer(o)) {
         TransformationMatrix t;
         getTransformFromContainer(o, containerOffset, t);
         transformState.applyTransform(t, preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
     } else {
         transformState.move(containerOffset.width(), containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
     }
@@ skipping 68 matching lines @@
     ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
     for (LayoutObject* child = startChild; child && child != endChild; ) {
         // Save our next sibling as moveChildTo will clear it.
         LayoutObject* nextSibling = child->nextSibling();
         moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
         child = nextSibling;
     }
 }
 
 } // namespace blink