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

Source/core/layout/compositing/CompositingReasonFinder.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CompositingReasonFinder_h
 #define CompositingReasonFinder_h
 
 #include "core/layout/compositing/CompositingTriggers.h"
 #include "platform/graphics/CompositingReasons.h"
+#include "wtf/Allocator.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
 class DeprecatedPaintLayer;
 class LayoutObject;
 class ComputedStyle;
 class LayoutView;
 
 class CompositingReasonFinder {
+    DISALLOW_ALLOCATION();
     WTF_MAKE_NONCOPYABLE(CompositingReasonFinder);
 public:
     explicit CompositingReasonFinder(LayoutView&);
 
     CompositingReasons potentialCompositingReasonsFromStyle(LayoutObject*) const;
     CompositingReasons directReasons(const DeprecatedPaintLayer*) const;
 
     void updateTriggers();
 
     bool hasOverflowScrollTrigger() const;
     bool requiresCompositingForScrollableFrame() const;
     bool requiresCompositingForAnimation(const ComputedStyle&) const;
 
 private:
     bool isMainFrame() const;
 
     CompositingReasons nonStyleDeterminedDirectReasons(const DeprecatedPaintLayer*) const;
 
     bool requiresCompositingForTransform(LayoutObject*) const;
     bool requiresCompositingForPositionFixed(const DeprecatedPaintLayer*) const;
 
     LayoutView& m_layoutView;
     CompositingTriggerFlags m_compositingTriggers;
 };
 
 } // namespace blink
 
 #endif // CompositingReasonFinder_h