When a pattern with invalid UTF-8 is given, the error message suggests unqualified use of hex escape sequences to match arbitrary bytes. But you *also* need to disable Unicode mode. So include that in the error message. Fixes #1339
When a pattern with invalid UTF-8 is given, the error message suggests unqualified use of hex escape sequences to match arbitrary bytes. But you *also* need to disable Unicode mode. So include that in the error message. Fixes #1339