function loadSinon(fnDone) {
		oFrameWindow.sap.ui.require(["sap/ui/thirdparty/sinon"], function (sinon) {
			if (!sinon) {
				setTimeout(function () {
					loadSinon(fnDone);
				}, 50);
			} else {
				fnDone();
			}
		});
	}
Firefox only function - load sinon as often as needed until it is defined.
@param {function} fnDone executed when sinon is loaded