If the action is not stateful then NULL will be returned. If the
action is stateful then the type of the return value is the type
given by Action.getStateType.
The return value (if non-NULL) should be freed with
Variant.unref when it is no longer required.
Queries the current state of action.
If the action is not stateful then NULL will be returned. If the action is stateful then the type of the return value is the type given by Action.getStateType.
The return value (if non-NULL) should be freed with Variant.unref when it is no longer required.