Embedded ajax-exercises throw JS error

[murhum1]

Submitting ajax-exercises throws a JS error when embedded into course material. When grading results come back, an a-plus-refresh-stats event is emitted, the handler for the event tries to update an #exercise-info element, which only exists on standalone exercise pages.

FIX: Add a check to see if the element is present before trying to run the .load function.

a-plus/exercise/templates/exercise/exercise.html

Lines 94 to 103 in 7290300

	window.addEventListener("message", function (event) {
	if (event.data.type === "a-plus-refresh-stats") {
	$("#submit-progress").addClass("hide");
	var $stats = $("#exercise-info"),
	url = $stats.data("url");
	$stats.load(url, function() {
	$stats.find('[data-toggle="tooltip"]').tooltip();
	});
	}
	});