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

Source/core/layout/svg/ReferenceFilterBuilder.h

Index: Source/core/layout/svg/ReferenceFilterBuilder.h
diff --git a/Source/core/layout/svg/ReferenceFilterBuilder.h b/Source/core/layout/svg/ReferenceFilterBuilder.h
index f520d90a167013a3822f5f24b4633d67bed7d5f4..16c02792927f36d25b5583c9e97eccf1079f97ad 100644
--- a/Source/core/layout/svg/ReferenceFilterBuilder.h
+++ b/Source/core/layout/svg/ReferenceFilterBuilder.h
@@ -32,6 +32,7 @@
 #define ReferenceFilterBuilder_h
 
 #include "core/fetch/DocumentResourceReference.h"
+#include "wtf/Allocator.h"
 #include "wtf/HashMap.h"
 #include "wtf/PassRefPtr.h"
 
@@ -44,6 +45,7 @@ class ReferenceFilterOperation;
 class ReferenceFilter;
 
 class ReferenceFilterBuilder {
+    STATIC_ONLY(ReferenceFilterBuilder);
 public:
     static DocumentResourceReference* documentResourceReference(const FilterOperation*);
     static void setDocumentResourceReference(const FilterOperation*, PassOwnPtr<DocumentResourceReference>);