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

Source/core/editing/EditingStrategy.h

Index: Source/core/editing/EditingStrategy.h
diff --git a/Source/core/editing/EditingStrategy.h b/Source/core/editing/EditingStrategy.h
index ab03db4333625ba7c12b542a5d2808f41e1110cd..9a533204ee573687c80ff458745fb2dc369b1f2e 100644
--- a/Source/core/editing/EditingStrategy.h
+++ b/Source/core/editing/EditingStrategy.h
@@ -8,6 +8,7 @@
 #include "core/CoreExport.h"
 #include "core/dom/NodeTraversal.h"
 #include "core/dom/shadow/ComposedTreeTraversal.h"
+#include "wtf/Allocator.h"
 
 namespace blink {
 
@@ -20,6 +21,7 @@ class PositionIteratorAlgorithm;
 // Editing algorithm defined on node traversal.
 template <typename Traversal>
 class CORE_TEMPLATE_CLASS_EXPORT EditingAlgorithm : public Traversal {
+    STATIC_ONLY(EditingAlgorithm);
 public:
     static int caretMaxOffset(const Node&);
     // TODO(yosin) We should make following functions to take |Node&| instead