Add null-correctness checking to [StrictTypeChecking] methods

Source/bindings/templates/methods.cpp

 {##############################################################################}
 {% macro generate_method(method, world_suffix) %}
 {% filter conditional(method.conditional_string) %}
 static void {{method.name}}{{method.overload_index}}Method{{world_suffix}}(const v8::FunctionCallbackInfo<v8::Value>& info)
 {
     {% if method.has_exception_state %}
     ExceptionState exceptionState(ExceptionState::ExecutionContext, "{{method.name}}", "{{interface_name}}", info.Holder(), info.GetIsolate());
     {% endif %}
     {% if method.name in ['addEventListener', 'removeEventListener'] %}
     {{add_remove_event_listener_method(method.name) | indent}}
@@ skipping 71 matching lines @@
    fewer arguments if they are omitted.
    Optional Dictionary arguments default to empty dictionary. #}
 if (UNLIKELY(info.Length() <= {{argument.index}})) {
     {{cpp_method_call(method, argument.v8_set_return_value, argument.cpp_value) | indent}}
     return;
 }
 {% endif %}
 {% if method.is_strict_type_checking and argument.is_wrapper_type %}
 {# Type checking for wrapper interface types (if interface not implemented,
    throw TypeError), per http://www.w3.org/TR/WebIDL/#es-interface #}
-if (info.Length() > {{argument.index}} && !isUndefinedOrNull(info[{{argument.index}}]) && !V8{{argument.idl_type}}::hasInstance(info[{{argument.index}}], info.GetIsolate(), worldType(info.GetIsolate()))) {
+if (info.Length() > {{argument.index}} && !{% if argument.is_nullable %}isUndefinedOrNull(info[{{argument.index}}]){% else %}info[{{argument.index}}]->IsUndefined(){% endif %} && !V8{{argument.idl_type}}::hasInstance(info[{{argument.index}}], info.GetIsolate(), worldType(info.GetIsolate()))) {
     {{throw_type_error(method, '"parameter %s is not of type \'%s\'."' %
                                (argument.index + 1, argument.idl_type)) | indent}}
     return;
 }
 {% endif %}
 {% if argument.is_callback_interface %}
 {% if argument.is_optional %}
 OwnPtr<{{argument.idl_type}}> {{argument.name}};
 if (info.Length() > {{argument.index}} && !isUndefinedOrNull(info[{{argument.index}}])) {
     if (!info[{{argument.index}}]->IsFunction()) {
@@ skipping 291 matching lines @@
     v8::Handle<v8::Object> wrapper = info.Holder();
     {% if is_constructor_raises_exception %}
     if (exceptionState.throwIfNeeded())
         return;
     {% endif %}
 
     V8DOMWrapper::associateObjectWithWrapper<{{v8_class}}>(impl.release(), &{{v8_class}}Constructor::wrapperTypeInfo, wrapper, info.GetIsolate(), WrapperConfiguration::Dependent);
     v8SetReturnValue(info, wrapper);
 }
 {% endmacro %}