Undefined variable no longer reported

It seems that as of 2v04.319 on both Linux and original Espruino Board 1.3, an undefined
variable does not result in a "UncaughtReference Error" message.

 ___                 _ 
|  __|___ ___ ___ _ _|_|___ ___ 
|  __|_ -| . |  _| | | |   | . |
|____|___|  _|_| |___|_|_|_|___|
         |_| espruino.com
 2v04.318 (c) 2019 G.Williams

Espruino is Open Source. Our work is supported
only by sales of official boards and donations:
http://espruino.com/Donate

>d
Uncaught ReferenceError: "d" is not defined
 at line 1 col 1
d
^
>

 ____                 _ 
|  __|___ ___ ___ _ _|_|___ ___ 
|  __|_ -| . |  _| | | |   | . |
|____|___|  _|_| |___|_|_|_|___|
         |_| espruino.com
 2v04.319 (c) 2019 G.Williams

Espruino is Open Source. Our work is supported
only by sales of official boards and donations:
http://espruino.com/Donate

>d
>