[heap] Limit friendship of the Heap class to essentials.

src/code-stubs.cc

 // Copyright 2012 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.
 
 #include "src/code-stubs.h"
 
 #include <sstream>
 
 #include "src/bootstrapper.h"
 #include "src/cpu-profiler.h"
@@ skipping 156 matching lines @@
 
     if (UseSpecialCache()) {
       AddToSpecialCache(new_object);
     } else {
       // Update the dictionary and the root in Heap.
       Handle<UnseededNumberDictionary> dict =
           UnseededNumberDictionary::AtNumberPut(
               Handle<UnseededNumberDictionary>(heap->code_stubs()),
               GetKey(),
               new_object);
-      heap->public_set_code_stubs(*dict);
+      heap->SetRootCodeStubs(*dict);
     }
     code = *new_object;
   }
 
   Activate(code);
   DCHECK(!NeedsImmovableCode() ||
          heap->lo_space()->Contains(code) ||
          heap->code_space()->FirstPage()->Contains(code->address()));
   return Handle<Code>(code, isolate());
 }
@@ skipping 878 matching lines @@
 
   if (type->Is(Type::UntaggedPointer())) {
     return Representation::External();
   }
 
   DCHECK(!type->Is(Type::Untagged()));
   return Representation::Tagged();
 }
 }  // namespace internal
 }  // namespace v8