Change update_forks_visibility_level into after_update hook in Project model

app/models/project.rb

@@ -61,6 +61,19 @@ class Project < ActiveRecord::Base
     update_column(:last_activity_at, self.created_at)
   end
+  # update visibility_levet of forks
+  after_update :update_forks_visibility_level
+  def update_forks_visibility_level
+    return unless visibility_level < visibility_level_was
+
+    forks.each do |forked_project|
+      if forked_project.visibility_level > visibility_level
+        forked_project.visibility_level = visibility_level
+        forked_project.save!
+      end
+    end
+  end
+
   ActsAsTaggableOn.strict_case_match = true
   acts_as_taggable_on :tags

app/services/projects/update_service.rb

@@ -13,7 +13,6 @@ module Projects
         end
         return false unless visibility_level_allowed?(new_visibility)
-        update_forks_visibility_level(new_visibility.to_i)
       end
       new_branch = params[:default_branch]
@@ -42,18 +41,5 @@ module Projects
       false
     end
-
-    def update_forks_visibility_level(new_level)
-      return unless new_level < project.visibility_level
-
-      project.forks.each do |forked_project|
-        fork_level = forked_project.visibility_level
-
-        if fork_level > new_level
-          forked_project.visibility_level = new_level
-          forked_project.save!
-        end
-      end
-    end
   end
 end