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

Source/core/layout/svg/LayoutSVGInlineText.h

 /*
  * Copyright (C) 2006 Oliver Hunt <ojh16@student.canterbury.ac.nz>
  * Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Rob Buis <buis@kde.org>
  *
  * 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.
  *
@@ skipping 52 matching lines @@
     LayoutRect clippedOverflowRectForPaintInvalidation(const LayoutBoxModelObject* paintInvalidationContainer, const PaintInvalidationState*) const final;
 
     float m_scalingFactor;
     Font m_scaledFont;
     SVGTextLayoutAttributes m_layoutAttributes;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutSVGInlineText, isSVGInlineText());
 
 class SVGInlineTextMetricsIterator {
+    DISALLOW_ALLOCATION();
 public:
     SVGInlineTextMetricsIterator() { reset(nullptr); }
 
     void advanceToTextStart(const LayoutSVGInlineText* textLayoutObject, unsigned startCharacterOffset)
     {
         ASSERT(textLayoutObject);
         if (m_textLayoutObject != textLayoutObject) {
             reset(textLayoutObject);
             ASSERT(!metricsList().isEmpty());
         }
@@ skipping 34 matching lines @@
     }
 
     const LayoutSVGInlineText* m_textLayoutObject;
     unsigned m_metricsListOffset;
     unsigned m_characterOffset;
 };
 
 }
 
 #endif // LayoutSVGInlineText_h