Avoid TLS load in AstNode constructor.

src/scopes.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 301 matching lines @@
   void Print(int n = 0);  // n = indentation; n < 0 => don't print recursively
 #endif
 
   // ---------------------------------------------------------------------------
   // Implementation.
  protected:
   friend class ParserFactory;
 
   explicit Scope(Type type);
 
+  Isolate* const isolate_;
+
   // Scope tree.
   Scope* outer_scope_;  // the immediately enclosing outer scope, or NULL
   ZoneList<Scope*> inner_scopes_;  // the immediately enclosed inner scopes
 
   // The scope type.
   Type type_;
 
   // Debugging support.
   Handle<String> scope_name_;
 
@@ skipping 99 matching lines @@
   }
 
   void SetDefaults(Type type,
                    Scope* outer_scope,
                    Handle<SerializedScopeInfo> scope_info);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCOPES_H_