[New Multicolumn] Simplified layout also needs to mark spanner placeholders for layout.

Source/core/layout/LayoutBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
  * License as published by the Free Software Foundation; either
@@ skipping 28 matching lines @@
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/layout/HitTestLocation.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutAnalyzer.h"
 #include "core/layout/LayoutDeprecatedFlexibleBox.h"
 #include "core/layout/LayoutFlexibleBox.h"
 #include "core/layout/LayoutFlowThread.h"
 #include "core/layout/LayoutGrid.h"
 #include "core/layout/LayoutInline.h"
+#include "core/layout/LayoutMultiColumnSpannerPlaceholder.h"
 #include "core/layout/LayoutObject.h"
 #include "core/layout/LayoutRegion.h"
 #include "core/layout/LayoutTableCell.h"
 #include "core/layout/LayoutTextCombine.h"
 #include "core/layout/LayoutTextControl.h"
 #include "core/layout/LayoutTextFragment.h"
 #include "core/layout/LayoutTheme.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/TextAutosizer.h"
 #include "core/layout/line/InlineIterator.h"
@@ skipping 1502 matching lines @@
         }
 
         // FIXME: Glyph overflow will get lost in this case, but not really a big deal.
         GlyphOverflowAndFallbackFontsMap textBoxDataMap;
         for (ListHashSet<RootInlineBox*>::const_iterator it = lineBoxes.begin(); it != lineBoxes.end(); ++it) {
             RootInlineBox* box = *it;
             box->computeOverflow(box->lineTop(), box->lineBottom(), textBoxDataMap);
         }
     } else {
         for (LayoutBox* box = firstChildBox(); box; box = box->nextSiblingBox()) {
-            if (!box->isOutOfFlowPositioned())
+            if (!box->isOutOfFlowPositioned()) {
+                if (box->isLayoutMultiColumnSpannerPlaceholder())
+                    toLayoutMultiColumnSpannerPlaceholder(box)->markForLayoutIfObjectInFlowThreadNeedsLayout();
                 box->layoutIfNeeded();
+            }
         }
     }
 }
 
 bool LayoutBlock::simplifiedLayout()
 {
     // Check if we need to do a full layout.
     if (normalChildNeedsLayout() || selfNeedsLayout())
         return false;
 
@@ skipping 2332 matching lines @@
 void LayoutBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const LayoutObject* obj) const
 {
     showLayoutObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink