Revert "Merge branch 'master' of https://github.com/discourse/discourse"

This reverts commit e62a85cf6f, reversing
changes made to 2660c2e21d.

lib/post_revisor.rb

@@ -567,7 +567,11 @@ class PostRevisor
   end
 
   def update_topic_excerpt
-    @topic.update_excerpt(@post.excerpt_for_topic)
+    excerpt = @post.excerpt_for_topic
+    @topic.update_column(:excerpt, excerpt)
+    if @topic.archetype == "banner"
+      ApplicationController.banner_json_cache.clear
+    end
   end
 
   def update_category_description