Improve error handling in streaming/index.js (#5968)

On an unhandled worker exception, we should log the exception
and exit with nonzero status, instead of letting workers
silently fail and restarting them in an endless loop.

Note: we previously tried to handle the `'error'` signal.
That's not a signal Node fires; my patch traps `'uncaughtException'`,
which is what the code was _trying_ to do.

streaming/index.js

@@ -563,12 +563,14 @@ const startWorker = (workerId) => {
 
   const onError = (err) => {
     log.error(err);
+    server.close();
+    process.exit(0);
   };
 
   process.on('SIGINT', onExit);
   process.on('SIGTERM', onExit);
   process.on('exit', onExit);
-  process.on('error', onError);
+  process.on('uncaughtException', onError);
 };
 
 throng({