lib: remove useless default caught

The variable caught's value is undefined, so the '|| caught' is
useless.

PR-URL: #12884
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Refael Ackermann <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
Reviewed-By: Ron Korving <[email protected]>
Reviewed-By: Daniel Bevenius <[email protected]>
Reviewed-By: Gibson Fahnestock <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: James M Snell <[email protected]>

lib/internal/bootstrap_node.js

@@ -297,7 +297,7 @@
       var caught;
 
       if (process.domain && process.domain._errorHandler)
-        caught = process.domain._errorHandler(er) || caught;
+        caught = process.domain._errorHandler(er);
 
       if (!caught)
         caught = process.emit('uncaughtException', er);