The source code

    /**
     * @class Ext.EventManager
     */
    Ext.apply(Ext.EventManager, function(){
    	var resizeEvent,
        	resizeTask,
        	textEvent,
        	textSize,
        	D = Ext.lib.Dom,
        	E = Ext.lib.Event,
        	propRe = /^(?:scope|delay|buffer|single|stopEvent|preventDefault|stopPropagation|normalized|args|delegate)$/,
            curWidth = 0,
            curHeight = 0,
            // note 1: IE fires ONLY the keydown event on specialkey autorepeat
            // note 2: Safari < 3.1, Gecko (Mac/Linux) & Opera fire only the keypress event on specialkey autorepeat
            // (research done by @Jan Wolter at http://unixpapa.com/js/key.html)
            useKeydown = Ext.isSafari ?
                        Ext.num(navigator.userAgent.toLowerCase().match(/version\/(\d+\.\d)/)[1] || 2) >= 3.1 :
                        !((Ext.isGecko && !Ext.isWindows) || Ext.isOpera);

    	return {
    		// private
    	    doResizeEvent: function(){
                var h = D.getViewHeight(),
                    w = D.getViewWidth();

                //whacky problem in IE where the resize event will fire even though the w/h are the same.
                if(curHeight != h || curWidth != w){
                    resizeEvent.fire(curWidth = w, curHeight = h);
                }
    	    },

    	    /**
    	     * Fires when the window is resized and provides resize event buffering (50 milliseconds), passes new viewport width and height to handlers.
    	     * @param {Function} fn        The method the event invokes
    	     * @param {Object}   scope    An object that becomes the scope of the handler
    	     * @param {boolean}  options
    	     */
    	    onWindowResize : function(fn, scope, options){
    	        if(!resizeEvent){
    	            resizeEvent = new Ext.util.Event();
    	            resizeTask = new Ext.util.DelayedTask(this.doResizeEvent);
    	            E.on(window, "resize", this.fireWindowResize, this);
    	        }
    	        resizeEvent.addListener(fn, scope, options);
    	    },

    	    // exposed only to allow manual firing
    	    fireWindowResize : function(){
    	        if(resizeEvent){
    	            if((Ext.isIE||Ext.isAir) && resizeTask){
    	                resizeTask.delay(50);
    	            }else{
    	                resizeEvent.fire(D.getViewWidth(), D.getViewHeight());
    	            }
    	        }
    	    },

    	    /**
    	     * Fires when the user changes the active text size. Handler gets called with 2 params, the old size and the new size.
    	     * @param {Function} fn        The method the event invokes
    	     * @param {Object}   scope    An object that becomes the scope of the handler
    	     * @param {boolean}  options
    	     */
    	    onTextResize : function(fn, scope, options){
    	        if(!textEvent){
    	            textEvent = new Ext.util.Event();
    	            var textEl = new Ext.Element(document.createElement('div'));
    	            textEl.dom.className = 'x-text-resize';
    	            textEl.dom.innerHTML = 'X';
    	            textEl.appendTo(document.body);
    	            textSize = textEl.dom.offsetHeight;
    	            setInterval(function(){
    	                if(textEl.dom.offsetHeight != textSize){
    	                    textEvent.fire(textSize, textSize = textEl.dom.offsetHeight);
    	                }
    	            }, this.textResizeInterval);
    	        }
    	        textEvent.addListener(fn, scope, options);
    	    },

    	    /**
    	     * Removes the passed window resize listener.
    	     * @param {Function} fn        The method the event invokes
    	     * @param {Object}   scope    The scope of handler
    	     */
    	    removeResizeListener : function(fn, scope){
    	        if(resizeEvent){
    	            resizeEvent.removeListener(fn, scope);
    	        }
    	    },

    	    // private
    	    fireResize : function(){
    	        if(resizeEvent){
    	            resizeEvent.fire(D.getViewWidth(), D.getViewHeight());
    	        }
    	    },

    	     /**
    	     * The frequency, in milliseconds, to check for text resize events (defaults to 50)
    	     */
    	    textResizeInterval : 50,

    	    /**
             * Url used for onDocumentReady with using SSL (defaults to Ext.SSL_SECURE_URL)
             */
            ieDeferSrc : false,

            // protected for use inside the framework
            // detects whether we should use keydown or keypress based on the browser.
            useKeydown: useKeydown
        };
    }());

    Ext.EventManager.on = Ext.EventManager.addListener;

    Ext.apply(Ext.EventObjectImpl.prototype, {
        /** Key constant @type Number */
        BACKSPACE: 8,
        /** Key constant @type Number */
        TAB: 9,
        /** Key constant @type Number */
        NUM_CENTER: 12,
        /** Key constant @type Number */
        ENTER: 13,
        /** Key constant @type Number */
        RETURN: 13,
        /** Key constant @type Number */
        SHIFT: 16,
        /** Key constant @type Number */
        CTRL: 17,
        CONTROL : 17, // legacy
        /** Key constant @type Number */
        ALT: 18,
        /** Key constant @type Number */
        PAUSE: 19,
        /** Key constant @type Number */
        CAPS_LOCK: 20,
        /** Key constant @type Number */
        ESC: 27,
        /** Key constant @type Number */
        SPACE: 32,
        /** Key constant @type Number */
        PAGE_UP: 33,
        PAGEUP : 33, // legacy
        /** Key constant @type Number */
        PAGE_DOWN: 34,
        PAGEDOWN : 34, // legacy
        /** Key constant @type Number */
        END: 35,
        /** Key constant @type Number */
        HOME: 36,
        /** Key constant @type Number */
        LEFT: 37,
        /** Key constant @type Number */
        UP: 38,
        /** Key constant @type Number */
        RIGHT: 39,
        /** Key constant @type Number */
        DOWN: 40,
        /** Key constant @type Number */
        PRINT_SCREEN: 44,
        /** Key constant @type Number */
        INSERT: 45,
        /** Key constant @type Number */
        DELETE: 46,
        /** Key constant @type Number */
        ZERO: 48,
        /** Key constant @type Number */
        ONE: 49,
        /** Key constant @type Number */
        TWO: 50,
        /** Key constant @type Number */
        THREE: 51,
        /** Key constant @type Number */
        FOUR: 52,
        /** Key constant @type Number */
        FIVE: 53,
        /** Key constant @type Number */
        SIX: 54,
        /** Key constant @type Number */
        SEVEN: 55,
        /** Key constant @type Number */
        EIGHT: 56,
        /** Key constant @type Number */
        NINE: 57,
        /** Key constant @type Number */
        A: 65,
        /** Key constant @type Number */
        B: 66,
        /** Key constant @type Number */
        C: 67,
        /** Key constant @type Number */
        D: 68,
        /** Key constant @type Number */
        E: 69,
        /** Key constant @type Number */
        F: 70,
        /** Key constant @type Number */
        G: 71,
        /** Key constant @type Number */
        H: 72,
        /** Key constant @type Number */
        I: 73,
        /** Key constant @type Number */
        J: 74,
        /** Key constant @type Number */
        K: 75,
        /** Key constant @type Number */
        L: 76,
        /** Key constant @type Number */
        M: 77,
        /** Key constant @type Number */
        N: 78,
        /** Key constant @type Number */
        O: 79,
        /** Key constant @type Number */
        P: 80,
        /** Key constant @type Number */
        Q: 81,
        /** Key constant @type Number */
        R: 82,
        /** Key constant @type Number */
        S: 83,
        /** Key constant @type Number */
        T: 84,
        /** Key constant @type Number */
        U: 85,
        /** Key constant @type Number */
        V: 86,
        /** Key constant @type Number */
        W: 87,
        /** Key constant @type Number */
        X: 88,
        /** Key constant @type Number */
        Y: 89,
        /** Key constant @type Number */
        Z: 90,
        /** Key constant @type Number */
        CONTEXT_MENU: 93,
        /** Key constant @type Number */
        NUM_ZERO: 96,
        /** Key constant @type Number */
        NUM_ONE: 97,
        /** Key constant @type Number */
        NUM_TWO: 98,
        /** Key constant @type Number */
        NUM_THREE: 99,
        /** Key constant @type Number */
        NUM_FOUR: 100,
        /** Key constant @type Number */
        NUM_FIVE: 101,
        /** Key constant @type Number */
        NUM_SIX: 102,
        /** Key constant @type Number */
        NUM_SEVEN: 103,
        /** Key constant @type Number */
        NUM_EIGHT: 104,
        /** Key constant @type Number */
        NUM_NINE: 105,
        /** Key constant @type Number */
        NUM_MULTIPLY: 106,
        /** Key constant @type Number */
        NUM_PLUS: 107,
        /** Key constant @type Number */
        NUM_MINUS: 109,
        /** Key constant @type Number */
        NUM_PERIOD: 110,
        /** Key constant @type Number */
        NUM_DIVISION: 111,
        /** Key constant @type Number */
        F1: 112,
        /** Key constant @type Number */
        F2: 113,
        /** Key constant @type Number */
        F3: 114,
        /** Key constant @type Number */
        F4: 115,
        /** Key constant @type Number */
        F5: 116,
        /** Key constant @type Number */
        F6: 117,
        /** Key constant @type Number */
        F7: 118,
        /** Key constant @type Number */
        F8: 119,
        /** Key constant @type Number */
        F9: 120,
        /** Key constant @type Number */
        F10: 121,
        /** Key constant @type Number */
        F11: 122,
        /** Key constant @type Number */
        F12: 123,

        /** @private */
        isNavKeyPress : function(){
            var me = this,
            	k = this.normalizeKey(me.keyCode);
            return (k >= 33 && k <= 40) ||  // Page Up/Down, End, Home, Left, Up, Right, Down
    		k == me.RETURN ||
    		k == me.TAB ||
    		k == me.ESC;
        },

        isSpecialKey : function(){
            var k = this.normalizeKey(this.keyCode);
            return (this.type == 'keypress' && this.ctrlKey) ||
    		this.isNavKeyPress() ||
            (k == this.BACKSPACE) || // Backspace
    		(k >= 16 && k <= 20) || // Shift, Ctrl, Alt, Pause, Caps Lock
    		(k >= 44 && k <= 45);   // Print Screen, Insert
        },

    	getPoint : function(){
    	    return new Ext.lib.Point(this.xy[0], this.xy[1]);
    	},

        /**
         * Returns true if the control, meta, shift or alt key was pressed during this event.
         * @return {Boolean}
         */
        hasModifier : function(){
            return ((this.ctrlKey || this.altKey) || this.shiftKey);
        }
    });