*
* @example
* var foo = element(by.id('foo'));
* expect(foo.isDisplayed()).toBe(false);
*
* @returns {!webdriver.promise.Promise.
} A promise that will be
* resolved with whether this element is currently visible on the page.
*/
webdriver.WebElement.prototype.isDisplayed = function() {};
/**
* Take a screenshot of the visible region encompassed by this element's
* bounding rectangle.
*
* @view
* Inner Text
*
* @example
* function writeScreenShot(data, filename) {
* var stream = fs.createWriteStream(filename);
* stream.write(new Buffer(data, 'base64'));
* stream.end();
* }
* var foo = element(by.id('foo'));
* foo.takeScreenshot().then((png) => {
* writeScreenShot(png, 'foo.png');
* });
*
* Note that this is a new feature in WebDriver and may not be supported by
* your browser's driver. It isn't yet supported in Chromedriver as of 2.21.
*
* @param {boolean=} opt_scroll Optional argument that indicates whether the
* element should be scrolled into view before taking a screenshot. Defaults
* to false.
* @returns {!webdriver.promise.Promise.} A promise that will be
* resolved to the screenshot as a base-64 encoded PNG.
*/
webdriver.WebElement.prototype.takeScreenshot = function(opt_scroll) {};