Update Chroot with crouton

My chroot on a flash drive has worked great for the past month of Chromebook tinkering. A recent update to ChromeOS prevented me from being able to log into a full-blown Unity GUI. Using crouton to perform a simple update to the chroot got me sorted out:
  1. Open a terminal (CTRL+ALT+T) and enter the shell by typing "shell" and pressing enter.
  2. Enter "sudo sh -e ~/Downloads/crouton -n trusty -u" (without the quotes) where trusty is the chroot name / Ubuntu version you have installed
  3. Let the stream of updates run and you should be able to launch your chroot again