It is a bug in how we figure out if a message is changed in Launchpad, so we let some slip in even if they should not be counted.
Technical details ahead :)
What happens is that with some old data, possibly resulting from message sharing migration, we've got a weird situation:
1. There is a shared translation which is both current and imported
2. There is a diverged translation which is only imported (and not current)
3. There is no diverged current translation
Technically, this one is a changed translation, because the current one (shared, imported one) is different from the most relevant imported translation (diverged one). However, since this is a situation one can't get into with the latest code, and considering how we want to get rid of all the divergence for imported messages (bug #456597), let's just not count them anyway.
It is a bug in how we figure out if a message is changed in Launchpad, so we let some slip in even if they should not be counted.
Technical details ahead :)
What happens is that with some old data, possibly resulting from message sharing migration, we've got a weird situation:
1. There is a shared translation which is both current and imported
2. There is a diverged translation which is only imported (and not current)
3. There is no diverged current translation
Technically, this one is a changed translation, because the current one (shared, imported one) is different from the most relevant imported translation (diverged one). However, since this is a situation one can't get into with the latest code, and considering how we want to get rid of all the divergence for imported messages (bug #456597), let's just not count them anyway.