Add grid/flex layout support for <fieldset>

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

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 291 matching lines @@
     , m_gridIsDirty(true)
     , m_orderIterator(this)
 {
     ASSERT(!childrenInline());
 }
 
 LayoutGrid::~LayoutGrid()
 {
 }
 
+LayoutGrid* LayoutGrid::createAnonymous(Document* document)
+{
+    LayoutGrid* layoutGrid = new LayoutGrid(nullptr);
+    layoutGrid->setDocumentForAnonymous(document);
+    return layoutGrid;
+}
+
 void LayoutGrid::addChild(LayoutObject* newChild, LayoutObject* beforeChild)
 {
     LayoutBlock::addChild(newChild, beforeChild);
 
     // The grid needs to be recomputed as it might contain auto-placed items that will change their position.
     dirtyGrid();
 }
 
 void LayoutGrid::removeChild(LayoutObject* child)
 {
@@ skipping 2280 matching lines @@
     return isOrthogonalChild(child) ? childLocation.transposedPoint() : childLocation;
 }
 
 void LayoutGrid::paintChildren(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) const
 {
     if (!m_gridItemArea.isEmpty())
         GridPainter(*this).paintChildren(paintInfo, paintOffset);
 }
 
 } // namespace blink