Will process the functions hooked into it.
The 'all' hook passes all of the arguments or parameters that were used for the hook, which this function was called for.
This function is used internally for ApplyFilterHook::apply(), DoActionHook::do, and DoActionHook::doRefArray() and is not meant to be used from outside those methods. This method does not check for the existence of the all hook, so it will fail unless the all hook exists prior to this method call.
The collected parameters from the hook that was called.