Don't explicitly declare display_name.

common/lib/xmodule/xmodule/capa_module.py

@@ -73,8 +73,6 @@ class CapaFields(object):
     input_state = Object(help="Dictionary for maintaining the state of inputtypes", scope=Scope.user_state)
     student_answers = Object(help="Dictionary with the current student responses", scope=Scope.user_state)
     done = Boolean(help="Whether the student has answered the problem", scope=Scope.user_state)
-    # display_name is used by the LMS on the sequential ribbon (displayed as a tooltip)
-    display_name = XModule.display_name
     seed = StringyInteger(help="Random seed for this student", scope=Scope.user_state)
     weight = StringyFloat(help="How much to weight this problem by", scope=Scope.settings)
     markdown = String(help="Markdown source of this module", scope=Scope.settings)

common/lib/xmodule/xmodule/html_module.py

@@ -19,8 +19,6 @@ log = logging.getLogger("mitx.courseware")
 
 class HtmlFields(object):
     data = String(help="Html contents to display for this module", scope=Scope.content)
-    # Used by the LMS on the sequential ribbon (displayed as a tooltip)
-    display_name = XModule.display_name
 
 
 class HtmlModule(HtmlFields, XModule):

common/lib/xmodule/xmodule/video_module.py

@@ -20,8 +20,6 @@ log = logging.getLogger(__name__)
 class VideoFields(object):
     data = String(help="XML data for the problem", scope=Scope.content)
     position = Integer(help="Current position in the video", scope=Scope.user_state, default=0)
-    # display_name is used by the LMS on the sequential ribbon (displayed as a tooltip)
-    display_name = XModule.display_name
 
 
 class VideoModule(VideoFields, XModule):