Should we abort the gateway on register_watch() failure?

[gbregman]

In the register_watch() code in state.py we have:

    def register_watch(self, notify_event):
        """Sets a watch on the OMAP object for changes."""

        def _watcher_callback(notify_id, notifier_id, watch_id, data):
            notify_event.set()

        if self.watch is None:
            try:
                self.watch = self.ioctx.watch(self.omap_name, _watcher_callback)
            except Exception:
                self.logger.exception(f"Unable to initiate watch")
        else:
            self.logger.info(f"Watch already exists.")

in case we got an exception in self.ioctx.watch() we display it to the log but continue working. So, in such a case we'll continue running the gateway but it won't get notifications about OMAP updates. We'll still run updates using the timer if this is enabled. So, we need to decide if we're OK with that or do we want to abort the gateway in such a case.