events: Handle emit('error') before ctor

The previous commit did not handle the case when the event type
is 'error', since that is checked before reading the handler.

lib/events.js

@@ -53,6 +53,9 @@ EventEmitter.prototype.setMaxListeners = function(n) {
 EventEmitter.prototype.emit = function(type) {
   var er, handler, len, args, i, listeners;
 
+  if (!this._events)
+    this._events = {};
+
   // If there is no 'error' event listener then throw.
   if (type === 'error') {
     if (!this._events.error ||
@@ -73,9 +76,6 @@ EventEmitter.prototype.emit = function(type) {
     }
   }
 
-  if (!this._events)
-    this._events = {};
-
   handler = this._events[type];
 
   if (typeof handler === 'undefined')

test/simple/test-event-emitter-subclass.js

@@ -38,6 +38,16 @@ var myee = new MyEE(function() {
   called = true;
 });
 
+
+util.inherits(ErrorEE, EventEmitter);
+function ErrorEE() {
+  this.emit('error', new Error('blerg'));
+}
+
+assert.throws(function() {
+  new ErrorEE();
+}, /blerg/);
+
 process.on('exit', function() {
   assert(called);
   console.log('ok');