Put SequenceDescriptor back as a subclass of MakeModuleDescriptor. THe previous change to have it derive from EditorDescriptor was not safe as EditorDescriptor presumes that there is a edit box in the JS save flows. So we need to edit get_context() on MakoModuleDescriptor to also pass along the metadata to the Mako rendering templates

common/lib/xmodule/xmodule/mako_module.py

@@ -31,7 +31,9 @@ class MakoModuleDescriptor(XModuleDescriptor):
         """
         Return the context to render the mako template with
         """
-        return {'module': self}
+        return {'module': self,
+                'metadata': self.metadata
+                }
 
     def get_html(self):
         return self.system.render_template(

common/lib/xmodule/xmodule/seq_module.py

@@ -112,7 +112,7 @@ class SequenceModule(XModule):
         return new_class
 
 
-class SequenceDescriptor(EditingDescriptor, XmlDescriptor):
+class SequenceDescriptor(MakoModuleDescriptor, XmlDescriptor):
     mako_template = 'widgets/sequence-edit.html'
     module_class = SequenceModule