Move visibility_level check for forked projects to Project model

app/helpers/visibility_level_helper.rb

@@ -89,7 +89,6 @@ module VisibilityLevelHelper
 
   def skip_level?(form_model, level)
     form_model.is_a?(Project) &&
-    form_model.forked? &&
-    !Gitlab::VisibilityLevel.allowed_fork_levels(form_model.forked_from_project.visibility_level).include?(level)
+    !form_model.visibility_level_allowed?(level)
   end
 end

app/models/project.rb

@@ -783,4 +783,9 @@ class Project < ActiveRecord::Base
     service.active = true
     service.save
   end
+
+  def visibility_level_allowed?(level)
+    return true unless forked?
+    Gitlab::VisibilityLevel.allowed_fork_levels(forked_from_project.visibility_level).include?(level)
+  end
 end