Comment 1 for bug 1950811

It seems that we were one upstream version behind on python-memcached, and that upstream version included https://github.com/linsomniac/python-memcached/pull/135, which added the flag to indicate that stored data corresponded to a text value. So we'll have to explicitly decode when we know that we expect to find text; I think that goes for most of our uses of memcache, except for `LaunchpadRootIndexView` which seems to store a pickled array (probably unintentionally as we normally prefer JSON to pickle whenever possible).