debugger: also exit when the repl emits 'exit'

Exit the debug repl when repl emits 'exit'

Refs: https://github.com/nodejs/node-v0.x-archive/issues/5637
Fixes: https://github.com/nodejs/node-v0.x-archive/issues/5631
PR-URL: https://github.com/nodejs/node/pull/2369
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/_debugger.js

@@ -1546,8 +1546,7 @@ Interface.prototype.repl = function() {
   var listeners = this.repl.rli.listeners('SIGINT').slice(0);
   this.repl.rli.removeAllListeners('SIGINT');
 
-  // Exit debug repl on Ctrl + C
-  this.repl.rli.once('SIGINT', function() {
+  function exitDebugRepl() {
     // Restore all listeners
     process.nextTick(function() {
       listeners.forEach(function(listener) {
@@ -1557,7 +1556,16 @@ Interface.prototype.repl = function() {
 
     // Exit debug repl
     self.exitRepl();
-  });
+
+    self.repl.rli.removeListener('SIGINT', exitDebugRepl);
+    self.repl.removeListener('exit', exitDebugRepl);
+  }
+
+  // Exit debug repl on SIGINT
+  this.repl.rli.on('SIGINT', exitDebugRepl);
+
+  // Exit debug repl on repl exit
+  this.repl.on('exit', exitDebugRepl);
 
   // Set new
   this.repl.eval = this.debugEval.bind(this);