explorer: Add a fixme to show when applications are trying to show a balloon tip in the taskbar notification area.

This does not mean to use the current cursor position. Instead, it means
that the left hand edge of balloon tips doesn't have to be exactly the
co-ordinate passed in (i.e. the stem can be as vertical as possible) and
it means non-balloon tips can use smart placement.

comctl32: Unify the implementation of TOOLTIPS_Show and TOOLTIPS_TrackShow to give tracked tooltips balloon support.

Check that there is a connection before trying to cancel it.

credui: Ensure that the foreground window doesn't get changed while the user is typing in their password.

This doesn't currently work on Wine as LockSetForegroundWindow isn't 
implemented, but when it does it should work nicely.