Move runtime helper for JSSet and JSMap onto objects.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index f1b9219d6a90aaafb3a67a421ecd2654e7c60886..6d547ef67ac4632056cd84871b183f39cae90ffb 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -9301,6 +9301,9 @@ class JSSet : public JSCollection {
  public:
   DECLARE_CAST(JSSet)
 
+  static void Initialize(Handle<JSSet> set, Isolate* isolate);
+  static void Clear(Handle<JSSet> set);
+
   // Dispatched behavior.
   DECLARE_PRINTER(JSSet)
   DECLARE_VERIFIER(JSSet)
@@ -9315,6 +9318,9 @@ class JSMap : public JSCollection {
  public:
   DECLARE_CAST(JSMap)
 
+  static void Initialize(Handle<JSMap> map, Isolate* isolate);
+  static void Clear(Handle<JSMap> map);
+
   // Dispatched behavior.
   DECLARE_PRINTER(JSMap)
   DECLARE_VERIFIER(JSMap)