[heap] Remove Marking::AnyToGrey and change its callers to use simple marking functions.

src/heap/marking.h

 // Copyright 2016 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_MARKING_H
 #define V8_MARKING_H
 
 #include "src/utils.h"
 
 namespace v8 {
@@ skipping 318 matching lines @@
     DCHECK(IsWhite(markbit));
     markbit.Set();
     markbit.Next().Set();
   }
 
   INLINE(static void GreyToBlack(MarkBit markbit)) {
     DCHECK(IsGrey(markbit));
     markbit.Next().Set();
   }
 
-  INLINE(static void AnyToGrey(MarkBit markbit)) {
-    markbit.Set();
-    markbit.Next().Clear();
-  }
-
   enum ObjectColor {
     BLACK_OBJECT,
     WHITE_OBJECT,
     GREY_OBJECT,
     IMPOSSIBLE_COLOR
   };
 
   static const char* ColorName(ObjectColor color) {
     switch (color) {
       case BLACK_OBJECT:
@@ skipping 17 matching lines @@
   }
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Marking);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_MARKING_H_