SYNOPSIS:

StructuredPushSupplier::subscription_change not called when subscription 
is removed.

      DESCRIPTION:

A StructuredPushSupplier implementation, connected to the notification 
service gets correctly called its subscription_change() method, with the 
correct added events list, when a consumer subscribes for an event. 
When, the subscription is removed, though, subscription_change() is not 
called.

The subscription management internally seems to keep track correctly of 
the events subscribed. When multiple consumers subscribe for the same 
event and are stopped one by one afterwards, the event type vanishes 
from the list returned by ProxyPushSupplier::obtain_subscribed_types() 
at the  right time. As yet another data point: The offer management 
works correctly for adding and removing offers for the test cases I came 
up so far.

       SAMPLE FIX/WORKAROUND:

(1) Test for subscriptions by using 
ProxyPushSupplier::obtain_subscribed_types() to test if consumers are 
still interested in an event type.
(2) Just produce the events unconditionally.