Proper fix for the issue exposed by r17459

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index e7567cd42dd37123f2c59976ea2dac5ee12e9079..2337b5ad809ed620e940663e8448422eb687f548 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7391,10 +7391,6 @@ class GlobalObject: public JSObject {
     return answer;
   }
 
-  // Ensure that the global object has a cell for the given property name.
-  static Handle<PropertyCell> EnsurePropertyCell(Handle<GlobalObject> global,
-                                                 Handle<Name> name);
-
   // Casting.
   static inline GlobalObject* cast(Object* obj);
 
@@ -7416,6 +7412,10 @@ class JSGlobalObject: public GlobalObject {
   // Casting.
   static inline JSGlobalObject* cast(Object* obj);
 
+  // Ensure that the global object has a cell for the given property name.
+  static Handle<PropertyCell> EnsurePropertyCell(Handle<JSGlobalObject> global,
+                                                 Handle<Name> name);
+
   // Dispatched behavior.
   DECLARE_PRINTER(JSGlobalObject)
   DECLARE_VERIFIER(JSGlobalObject)