anchor.diff:  
   enum NamingScope {
     global,
  -  instance
  +  instance,
  +  constant
   }
positive.code:     jsAst.Name result = constantNames[constant];
      if (result == null) {
        String longName = constantLongName(constant);
        result = getFreshName(NamingScope.global, longName);
        constantNames[constant] = result;
      }
      return result;
  
negative.code:   Map<String, String> getSuggestedNames(NamingScope scope) {
      if (scope == NamingScope.global) {
        return suggestedGlobalNames;
      } else if (scope == NamingScope.instance) {
        return suggestedInstanceNames;
      } else {
        assert(scope == NamingScope.constant);
        return const {};
      }
    }
  
  