Function set_needs_contents:
Defined in module m_drink_container (file: /std/modules/m_drink_container.c)

If needs_contents is 1, then the container can only be drunk from if it
contains a drink.  Otherwise the 'drink' is assumed to be handled as
part of the container itself (either by also inheriting M_DRINKABLE or
otherwise).

Prototype:
void set_needs_contents(int x);
