[runtime] Turn MigrateFastTo* into static helpers

src/objects.h

 // Copyright 2015 the V8 project 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 V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 2480 matching lines @@
   // Gets the number of currently used elements.
   int GetFastElementsUsage();
 
   static bool AllCanRead(LookupIterator* it);
   static bool AllCanWrite(LookupIterator* it);
 
  private:
   friend class JSReceiver;
   friend class Object;
 
-  static void MigrateFastToFast(Handle<JSObject> object, Handle<Map> new_map);
-  static void MigrateFastToSlow(Handle<JSObject> object,
-                                Handle<Map> new_map,
-                                int expected_additional_properties);
-
   // Used from Object::GetProperty().
   MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithFailedAccessCheck(
       LookupIterator* it);
 
   MUST_USE_RESULT static Maybe<bool> SetPropertyWithFailedAccessCheck(
       LookupIterator* it, Handle<Object> value, ShouldThrow should_throw);
 
   // Add a property to a slow-case object.
   static void AddSlowProperty(Handle<JSObject> object,
                               Handle<Name> name,
@@ skipping 8340 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_