FIX: We were overriding the canCreateTopicOnCategory computed property

It seems to be set everytime by the route so the old CP was not
required. This is not allowed in newer versions of ember.

app/assets/javascripts/discourse/app/controllers/discovery/topics.js

@@ -27,6 +27,7 @@ const controllerOpts = {
   router: service(),
 
   period: null,
+  canCreateTopicOnCategory: null,
 
   canStar: alias("currentUser.id"),
   showTopicPostBadges: not("discoveryTopics.new"),
@@ -158,11 +159,6 @@ const controllerOpts = {
   weekly: equal("period", "weekly"),
   daily: equal("period", "daily"),
 
-  @discourseComputed("model")
-  canCreateTopicOnCategory(model) {
-    return model.can_create_topic;
-  },
-
   @discourseComputed("allLoaded", "model.topics.length")
   footerMessage(allLoaded, topicsLength) {
     if (!allLoaded) {