Code review comment for lp:~igors/do-plugins/Thunderbird-fix

Hey Chris - I clicked "upgrade" half a dozen times now but I'm not sure it's changed anything (upgrade button is still available and the repo is still marked as RepositoryFormatKnitPack6RichRoot (bzr 1.9)). Please let me know if this still does not work for you and I'll try to do the merge to the trunk locally or just re-publish it as a new branch (I still have the branch sources that I seem to be able to work with).

As for EmailList class, the primary motivation for it was overwriting Add method so that I didn't have to check if the key was already present in the Dictionary whenever I needed to update "popularity" value.