Better error handling on general errors in the test window

[tbosch]

Error event listener for general errors in iframes.

Something like this should do the trick (jasmine specific though...)

    var errors;
    uit.append(function (window, $) {
        window.onerror = function (event) {
            errors.push(event);
        };

    });
    beforeEach(function() {
        errors = [];
    });
    afterEach(function() {
        expect(errors).toEqual([]);
    });