Move IncrementalRecordWrite to a stub.

src/incremental-marking.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 34 matching lines @@
     COMPLETE
   };
 
   static State state() {
     ASSERT(state_ == STOPPED || FLAG_incremental_marking);
     return state_;
   }
 
   static inline bool IsStopped() { return state() == STOPPED; }
 
+  static bool WorthActivating();
+
   static void Start();
 
   static void Stop();
 
   static void Hurry();
 
   static void Finalize();
 
   static void MarkingComplete();
 
@@ skipping 98 matching lines @@
   }
 
  private:
   static State state_;
   static MarkingStack marking_stack_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_INCREMENTAL_MARKING_H_