IDL compiler: [Default] arguments

Source/bindings/templates/methods.cpp

 {##############################################################################}
 {% macro generate_method(method) %}
 static void {{method.name}}Method(const v8::FunctionCallbackInfo<v8::Value>& args)
 {
     {% if method.number_of_required_arguments %}
     if (UNLIKELY(args.Length() < {{method.number_of_required_arguments}})) {
         throwTypeError(ExceptionMessages::failedToExecute("{{method.name}}", "{{interface_name}}", ExceptionMessages::notEnoughArguments({{method.number_of_required_arguments}}, args.Length())), args.GetIsolate());
         return;
     }
     {% endif %}
     {{cpp_class_name}}* imp = {{v8_class_name}}::toNative(args.Holder());
     {% for argument in method.arguments %}
-    {% if argument.is_optional %}
+    {% if argument.is_optional and not argument.has_default %}
     if (UNLIKELY(args.Length() <= {{argument.index}})) {
         {{argument.cpp_method}};
         return;
     }
     {% endif %}
     {% if argument.is_clamp %}
     {# FIXME: use C++ type for local variable #}
     {{argument.idl_type}} {{argument.name}} = 0;
     V8TRYCATCH_VOID(double, {{argument.name}}NativeValue, args[{{argument.index}}]->NumberValue());
     if (!std::isnan({{argument.name}}NativeValue))
@@ skipping 39 matching lines @@
 
 {##############################################################################}
 {% macro method_callback(method) %}
 static void {{method.name}}MethodCallback(const v8::FunctionCallbackInfo<v8::Value>& args)
 {
     TRACE_EVENT_SET_SAMPLING_STATE("Blink", "DOMMethod");
     {{cpp_class_name}}V8Internal::{{method.name}}Method(args);
     TRACE_EVENT_SET_SAMPLING_STATE("V8", "Execution");
 }
 {% endmacro %}