Move hash code from hidden string to a private symbol

src/isolate.h

 // 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.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include <queue>
 #include "include/v8-debug.h"
 #include "src/allocation.h"
@@ skipping 1115 matching lines @@
   v8::ArrayBuffer::Allocator* array_buffer_allocator() const {
     return array_buffer_allocator_;
   }
 
  protected:
   explicit Isolate(bool enable_serializer);
 
  private:
   friend struct GlobalState;
   friend struct InitializeGlobalState;
+  Handle<JSObject> SetUpSubregistry(Handle<JSObject> registry, Handle<Map> map,
+                                    const char* name);
 
   // These fields are accessed through the API, offsets must be kept in sync
   // with v8::internal::Internals (in include/v8.h) constants. This is also
   // verified in Isolate::Init() using runtime checks.
   void* embedder_data_[Internals::kNumIsolateDataSlots];
   Heap heap_;
 
   // The per-process lock should be acquired before the ThreadDataTable is
   // modified.
   class ThreadDataTable {
@@ skipping 432 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_