`bzr upgrade` in a lightweight checkout upgrades the parent branch

[Dato Simó]

<dato> running `bzr upgrade` in a lightweight checkout makes a backup of
       the light .bzr, not of the real .bzr. would that be considered a bug?
<lifeless> no, because its upgrading the lightweight checkout
<dato> but it changes the "remote" branch as well
<lifeless> ok thats a bug
<lifeless> it should only alter the lightweight checkout
<dato> okay, I'll double-check it does that, and file one

To reproduce:

  % bzr init --<old format> branch
  % bzr info branch | head -1
  Standalone tree (format: <old format>)

  % bzr checkout --lightweight branch checkout
  % cd checkout && bzr upgrade
  [...] finished

  % cd ../branch && bzr info | head -1
  Standalone tree (format: <current default>)

[Jelmer Vernooij (jelmer)]

This is already fixed:

This is a checkout. The branch (PATH) needs to be upgraded separately.
The bzrdir format Meta directory format 1 is already at the most recent format.