conditionally try to stop reverse deps, since other reverse deps may …

…have already stopped it

src/capabilities/server.py

@@ -624,6 +624,10 @@ def __stop_capability(self, name):
         capability = self.__capability_instances[name]
         rdepends = get_reverse_depends(name, self.__capability_instances.values())
         for cap in rdepends:
+            if cap.state in ['stopping', 'terminated']:
+                # It is possible that this cap was stopped by another cap in this list
+                continue
+            rospy.loginfo("Capability '{0}' being stopped because its dependency '{1}' is being stopped.".format(cap.name, name))
             self.__stop_capability(cap.interface)
         capability.stopped()
         self.__launch_manager.stop_capability_provider(capability.pid)