Use CourseDescriptor instead of HiddenDescriptor.

common/lib/xmodule/xmodule/course_module.py

@@ -16,7 +16,7 @@ class CourseDescriptor(SequenceDescriptor):
         return "/".join([self.location.org, self.location.course, self.location.name])
 
     @property
-    def name(self):
+    def display_name(self):
         self.metadata['display_name']
 
     def get_about_section(self, section_key):

common/lib/xmodule/xmodule/modulestore/xml.py

@@ -87,7 +87,8 @@ class XMLModuleStore(ModuleStore):
                             self.used_slugs.add(slug)
                             xml_data.set('slug', slug)
 
-                        module = XModuleDescriptor.load_from_xml(etree.tostring(xml_data), self, org, course, modulestore.default_class)
+                        from xmodule.course_module import CourseDescriptor
+                        module = XModuleDescriptor.load_from_xml(etree.tostring(xml_data), self, org, course, CourseDescriptor)
                         modulestore.modules[module.location] = module
 
                         if modulestore.eager: