Code review comment for lp:~paelzer/curtin/bug-1574113-derived-repositories

for disable_pockets, it looks to me like the string provided always has the release prepended.
for example:
 disable_pockets = [updates]
will disable 'trusty-updates'.

that makes sense.
but for:
  disable_pockets = ["mypocket", "unstable"]
this doesnt make so much sense.
I dont know how easily to do this other than special casing the words:
 updates, release, security, backports

also, might want to just check that this content from my /etc/apt/sources.list.d/google-chrome.list works as expected:
 deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main