code: function (config) {
  			var _config = objectAssign({}, { timeout: this.api.globals.waitForConditionTimeout }, config);
  			this.waitForElementVisible('@signinScreen', _config.timeout);
  			this.api.pause(self.screenTransitionTimeout);
  			return this;
  		}
docs: Waits for the signin screen UI to be visible.
  
  @param {Object} config The config spec.
  @param {number} config.timeout Optional timeout to wait for.