coverity#982161 unchecked return value

Change-Id: I3c8370915898e322f40812b52929132e192b3a2c

editeng/source/accessibility/AccessibleImageBullet.cxx

@@ -207,7 +207,19 @@ namespace accessibility
     {
 
         if( getNotifierClientId() != -1 )
-            ::comphelper::AccessibleEventNotifier::removeEventListener( getNotifierClientId(), xListener );
+        {
+            const sal_Int32 nListenerCount = ::comphelper::AccessibleEventNotifier::removeEventListener( getNotifierClientId(), xListener );
+            if ( !nListenerCount )
+            {
+                // no listeners anymore
+                // -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
+                // and at least to us not firing any events anymore, in case somebody calls
+                // NotifyAccessibleEvent, again
+                ::comphelper::AccessibleEventNotifier::TClientId nId( getNotifierClientId() );
+                mnNotifierClientId = -1;
+                ::comphelper::AccessibleEventNotifier::revokeClient( nId );
+            }
+        }
     }
 
     sal_Bool SAL_CALL AccessibleImageBullet::containsPoint( const awt::Point& rPoint ) throw (uno::RuntimeException, std::exception)