Implement argument definition test in the vm.

runtime/lib/object.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/bootstrap_natives.h"
 
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 
@@ skipping 25 matching lines @@
   // found.
   Class& instance_class = Class::Handle(instance.clazz());
   Function& function =
       Function::Handle(instance_class.LookupDynamicFunction(function_name));
   while (function.IsNull()) {
     instance_class = instance_class.SuperClass();
     if (instance_class.IsNull()) break;
     function = instance_class.LookupDynamicFunction(function_name);
   }
   if (!function.IsNull()) {
-    const int total_num_parameters =
-        function.num_fixed_parameters() + function.num_optional_parameters();
+    const int total_num_parameters = function.NumberOfParameters();
     const Array& array = Array::Handle(Array::New(total_num_parameters - 1));
     // Skip receiver.
     for (int i = 1; i < total_num_parameters; i++) {
       array.SetAt(i - 1, String::Handle(function.ParameterNameAt(i)));
     }
     dart_arguments.Add(&array);
   }
   Exceptions::ThrowByType(Exceptions::kNoSuchMethod, dart_arguments);
   return Object::null();
 }
 
 }  // namespace dart