Use standard EventTarget interface for events

core/util/eventtarget.js

@@ -0,0 +1,40 @@
+/*
+ * noVNC: HTML5 VNC client
+ * Copyright 2017 Pierre Ossman for Cendio AB
+ * Licensed under MPL 2.0 (see LICENSE.txt)
+ *
+ * See README.md for usage and integration instructions.
+ */
+
+var EventTargetMixin = {
+    _listeners: null,
+
+   addEventListener: function(type, callback) {
+      if (!this._listeners) {
+         this._listeners = new Map();
+      }
+      if (!this._listeners.has(type)) {
+         this._listeners.set(type, new Set());
+      }
+      this._listeners.get(type).add(callback);
+   },
+
+   removeEventListener: function(type, callback) {
+      if (!this._listeners || !this._listeners.has(type)) {
+         return;
+      }
+      this._listeners.get(type).delete(callback);
+   },
+
+   dispatchEvent: function(event) {
+      if (!this._listeners || !this._listeners.has(event.type)) {
+         return true;
+      }
+      this._listeners.get(event.type).forEach(function (callback) {
+         callback.call(this, event);
+      }, this);
+      return !event.defaultPrevented;
+   },
+};
+
+export default EventTargetMixin;

core/util/polyfill.js

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+/*
+ * noVNC: HTML5 VNC client
+ * Copyright 2017 Pierre Ossman for noVNC
+ * Licensed under MPL 2.0 or any later version (see LICENSE.txt)
+ */
+
+/* Polyfills to provide new APIs in old browsers */
+
+/* Object.assign() (taken from MDN) */
+if (typeof Object.assign != 'function') {
+    // Must be writable: true, enumerable: false, configurable: true
+    Object.defineProperty(Object, "assign", {
+        value: function assign(target, varArgs) { // .length of function is 2
+            'use strict';
+            if (target == null) { // TypeError if undefined or null
+                throw new TypeError('Cannot convert undefined or null to object');
+            }
+
+            var to = Object(target);
+
+            for (var index = 1; index < arguments.length; index++) {
+                var nextSource = arguments[index];
+
+                if (nextSource != null) { // Skip over if undefined or null
+                    for (var nextKey in nextSource) {
+                        // Avoid bugs when hasOwnProperty is shadowed
+                        if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
+                            to[nextKey] = nextSource[nextKey];
+                        }
+                    }
+                }
+            }
+            return to;
+        },
+        writable: true,
+        configurable: true
+    });
+}
+
+/* CustomEvent constructor (taken from MDN) */
+(function () {
+    function CustomEvent ( event, params ) {
+        params = params || { bubbles: false, cancelable: false, detail: undefined };
+        var evt = document.createEvent( 'CustomEvent' );
+        evt.initCustomEvent( event, params.bubbles, params.cancelable, params.detail );
+        return evt;
+    }
+
+    CustomEvent.prototype = window.Event.prototype;
+
+    if (typeof window.CustomEvent !== "function") {
+        window.CustomEvent = CustomEvent;
+    }
+})();