Bug#19799 delimiter command not working correctly when sourcing a sql file

- Client side readline functions unconditionally search for Unix '\n' line
endings. In this case, the delimiter statement was set to '//\r' instead 
of the intended '//'. When removing the '\n' check for and remove 
preceeding '\r' character as well.

mysql-test/r/mysql.result

@@ -36,6 +36,10 @@ Tables_in_test
 t1
 t2
 t3
+Database
+information_schema
+mysql
+test
 _
 Test delimiter : from command line
 a