Given the error, it is most likely indeed that your system ran out of memory. Chrome does tend to do that :P
There is not much we can do here, sadly enough. A system out of memory presents a real challenge to every game .. best we can do we did: tell you your system is out of memory and .. hope for the best :D
I hope you didn't lose much progress because of this. But for now, I am going to close this ticket. If it happens again while you are sure the system was not out of memory, to let us know!