BP_Group_Extension is fatally broken

[dwenaus]

plugins that rely on the group extension API become fatally broken with the latest release.

line 1204 of bp-groups-classes.php

Make sure user has access
if ( !$bp->is_item_admin )

return false;

needs to change because if the user does not have access, then we never get to the next part of the code on line 1222 where the nav item is inserted.

Solution, the if statement should not return false, it should be wrapped around lines 1207 to 1220.

This breaks many active plugins so is a HIGH priority for a quick 1.2.6.1 release.

[r-a-y]

Duplicate of #2730.
See #2701.