Make classes and structures in core/layout fast-allocated.

Source/core/layout/svg/SVGTextMetrics.h

 /*
  * Copyright (C) Research In Motion Limited 2010-2012. 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #ifndef SVGTextMetrics_h
 #define SVGTextMetrics_h
 
 #include "platform/text/TextDirection.h"
+#include "wtf/Allocator.h"
 
 namespace blink {
 
 class LayoutSVGInlineText;
 class TextRun;
 
 class SVGTextMetrics {
+    ALLOW_ONLY_INLINE_ALLOCATION();
 public:
     enum MetricsType {
         SkippedSpaceMetrics
     };
 
     SVGTextMetrics();
     SVGTextMetrics(MetricsType);
     SVGTextMetrics(LayoutSVGInlineText*, unsigned length, float width);
 
     static SVGTextMetrics measureCharacterRange(LayoutSVGInlineText*, unsigned position, unsigned length, TextDirection);
@@ skipping 11 matching lines @@
     SVGTextMetrics(LayoutSVGInlineText*, const TextRun&);
 
     float m_width;
     float m_height;
     unsigned m_length;
 };
 
 } // namespace blink
 
 #endif