isTooltipVisible = function(oTooltip, assert) {
		var $Tooltip = oTooltip.$();
		assert.equal($Tooltip.length, 1, "Tooltip " + oTooltip + " in DOM");
		assert.ok($Tooltip.is(":visible"), oTooltip.getId() + " is visible");
	}
Checks if the given tooltip is in DOM and visible

@param  {sap.ui.core.TooltipBase} oTooltip is the bastard to be checked
@return {boolean} true if the tooltip is visible