Perf improvement of new event handlig code.

lib/delegate.js

@@ -29,6 +29,9 @@ function Delegate(root) {
 
   /** @type function() */
   this.handle = Delegate.prototype.handle.bind(this);
+
+  // Cache of event listeners removed during an event cycle
+  this._removedListeners = [];
 }
 
 /**
@@ -239,6 +242,7 @@ Delegate.prototype.off = function(eventType, selector, handler, useCapture) {
     listener = listenerList[i];
 
     if ((!selector || selector === listener.selector) && (!handler || handler === listener.handler)) {
+      this._removedListeners.push(listener);
       listenerList.splice(i, 1);
     }
   }
@@ -346,9 +350,11 @@ Delegate.prototype.handle = function(event) {
     target = target.parentElement;
   }
 
+  var ret;
+
   for(i=0; i<toFire.length; i++) {
     // Has it been removed during while the event function was fired
-    if(listenerList.indexOf(toFire[i][2]) < 0) {
+    if(this._removedListeners.indexOf(toFire[i][2]) > -1) {
       continue;
     }
     returned = this.fire.apply(this, toFire[i]);
@@ -359,9 +365,12 @@ Delegate.prototype.handle = function(event) {
     if (returned === false) {
       toFire[i][0][EVENTIGNORE] = true;
       toFire[i][0].preventDefault();
-      return false;
+      ret = false;
+      break;
     }
   }
+
+  return ret;
 };
 
 /**