bool is_favourite) throws PropertyError
Change whether the contact is a user-defined favourite.
It's preferred to call this rather than setting FavouriteDetails.is_favourite directly, as this method gives error notification and will only return once the favouriteness has been written to the relevant backing store (or the operation's failed).
| is_favourite | `true` if the contact is a favourite; `false` otherwise |
| PropertyError | if setting the favouriteness failed |
0.6.2