Monte Hurd, 23/08/2014 21:04:
When the TOC is closed it would use the one on the left, and when open the one on the right (see attachment). (Reversed for RTL langs of course)
It's understandably hard to find a good icon for the concept of TOC (thanks for working on it!), but I must say I'm not quite certain the icon you attached conveys any meaning to me, let alone the inward/outward arrow. I'm just one person, but nobody seems to have replied so I figured better 1 than 0. :-)
Nemo