Fix showing of examples.

        var example = this.getExample(url);

        this.getViewport().setPageTitle(example.text);

        if (this.activeUrl !== url) {

            this.activateExampleCard();

            var ifr = document.getElementById("exampleIframe");

            ifr.contentWindow.location.replace('extjs/examples/' + example.url);

            setTimeout(this.activateExampleCard, 150); // Prevent previous example from flashing up

        }

        else {

            this.activateExampleCard();