[New Multicolumn] Let a spanner's containing block be the multicol container.

Source/core/rendering/RenderMultiColumnSpannerSet.cpp

Index: Source/core/rendering/RenderMultiColumnSpannerSet.cpp
diff --git a/Source/core/rendering/RenderMultiColumnSpannerSet.cpp b/Source/core/rendering/RenderMultiColumnSpannerSet.cpp
deleted file mode 100644
index 69ae4f36398f84e73fb69e9fb029b7a511a12baf..0000000000000000000000000000000000000000
--- a/Source/core/rendering/RenderMultiColumnSpannerSet.cpp
+++ /dev/null
@@ -1,36 +0,0 @@
-// 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.
-
-#include "config.h"
-#include "core/rendering/RenderMultiColumnSpannerSet.h"
-
-namespace blink {
-
-RenderMultiColumnSpannerSet* RenderMultiColumnSpannerSet::createAnonymous(RenderMultiColumnFlowThread* flowThread, RenderStyle* parentStyle, RenderBox* rendererInFlowThread)
-{
-    RenderMultiColumnSpannerSet* newSpanner = new RenderMultiColumnSpannerSet(flowThread, rendererInFlowThread);
-    Document& document = flowThread->document();
-    newSpanner->setDocumentForAnonymous(&document);
-    RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parentStyle, BLOCK);
-    newSpanner->setStyle(newStyle);
-    return newSpanner;
-}
-
-RenderMultiColumnSpannerSet::RenderMultiColumnSpannerSet(RenderMultiColumnFlowThread* flowThread, RenderBox* rendererInFlowThread)
-    : RenderMultiColumnSet(flowThread)
-    , m_rendererInFlowThread(rendererInFlowThread)
-{
-}
-
-bool RenderMultiColumnSpannerSet::recalculateColumnHeight(BalancedHeightCalculation calculationMode)
-{
-    return false;
-}
-
-const char* RenderMultiColumnSpannerSet::renderName() const
-{
-    return "RenderMultiColumnSpannerSet";
-}
-
-}