Add indicators to thread list view for staff posts and staff responses.

lms/static/coffee/src/discussion/content.coffee

@@ -127,7 +127,21 @@ if Backbone?
 
     toJSON: ->
       json_attributes = _.clone(@attributes)
-      _.extend(json_attributes, { title: @display_title(), body: @display_body() })
+      extended_attributes =
+        title: @display_title()
+        body: @display_body()
+        isStaffPost: @isStaffPost()
+        hasStaffResponse: @hasStaffResponse()
+      _.extend(json_attributes, extended_attributes)
+
+    isStaffPost: ->
+      DiscussionUtil.isStaff(@get("user_id"))
+
+    hasStaffResponse: ->
+      _.map(@get('responded_user_ids'), (id)->
+        DiscussionUtil.isStaff(id)).reduce((a,b)->
+        a or b
+      , false)
 
   class @Comment extends @Content
     urlMappers:

lms/templates/discussion/_underscore_templates.html

@@ -129,6 +129,12 @@
 
 <script type="text/template" id="thread-list-item-template">
     <a href="${'<%- id %>'}" data-id="${'<%- id %>'}">
+        ${"<% if (isStaffPost) { %>"}
+        <span class="staff-post-icon" data-tooltip="Staff Post"></span>
+        ${"<% }%>"}
+        ${"<% if (hasStaffResponse) { %>"}
+        <span class="staff-response-icon" data-tooltip="Staff Response"></span>
+        ${"<% }%>"}
         <span class="title">${"<%- title %>"}</span>
         ${"<% if (unread_comments_count > 0) { %>"}
             <span class="comments-count unread" data-tooltip="${"<%- unread_comments_count %>"} new comment${"<%- unread_comments_count > 1 ? 's' : '' %>"}">${"<%- comments_count %>"}</span>