Fix blink_perf.paint regression about tables

third_party/WebKit/Source/core/layout/LayoutTable.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2013 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
@@ skipping 1468 matching lines @@
 LayoutTableCell* LayoutTable::cellBefore(const LayoutTableCell* cell) const {
   recalcSectionsIfNeeded();
 
   LayoutTableSection* section = cell->section();
   unsigned effCol =
       absoluteColumnToEffectiveColumn(cell->absoluteColumnIndex());
   if (!effCol)
     return nullptr;
 
   // If we hit a colspan back up to a real cell.
-  LayoutTableSection::CellStruct& prevCell =
-      section->cellAt(cell->rowIndex(), effCol - 1);
-  return prevCell.primaryCell();
+  return section->primaryCellAt(cell->rowIndex(), effCol - 1);
 }
 
 LayoutTableCell* LayoutTable::cellAfter(const LayoutTableCell* cell) const {
   recalcSectionsIfNeeded();
 
   unsigned effCol = absoluteColumnToEffectiveColumn(
       cell->absoluteColumnIndex() + cell->colSpan());
   return cell->section()->primaryCellAt(cell->rowIndex(), effCol);
 }
 
@@ skipping 186 matching lines @@
 }
 
 LayoutUnit LayoutTable::paddingRight() const {
   if (collapseBorders())
     return LayoutUnit();
 
   return LayoutBlock::paddingRight();
 }
 
 }  // namespace blink