Don't use the Route model in migrations

db/migrate/20161130095245_fill_routes_table.rb

@@ -16,6 +16,6 @@ class FillRoutesTable < ActiveRecord::Migration
   end
 
   def down
-    Route.delete_all(source_type: 'Namespace')
+    execute("DELETE FROM routes WHERE source_type = 'Namespace'")
   end
 end

db/migrate/20161130101252_fill_projects_routes_table.rb

@@ -17,6 +17,6 @@ class FillProjectsRoutesTable < ActiveRecord::Migration
   end
 
   def down
-    Route.delete_all(source_type: 'Project')
+    execute("DELETE FROM routes WHERE source_type = 'Project'")
   end
 end