TOC counts deleted answers even if the user can't see them

[ArtOfCode-]

meta:289241

Table of contents appears to count deleted answers when counting how many answers are present (and hence whether it should display or not). If enough deleted answers are present, the TOC will display even if the user can't see those answers; if no live answers remain, the TOC is displayed but doesn't work for these users.

We should make sure the TOC isn't counting deleted answers.