GUI not working after updating to 18.04

I have updated the Ubuntu to latest i.e. 18.04. Looks like it broke something, now I am not able to get started with the log-in screen.

Link for the error:- https://drive.google.com/open?id=1bHglwmJWxTB4dD0lyJhIXAhrQR1LH8_J

Can someone please help me on this one?