function xml(assert, aContent) {
		var oDocument = XMLHelper.parse(aContent.join(``));

		assert.strictEqual(oDocument.parseError.errorCode, 0, `XML parsed correctly`);
		return oDocument.documentElement;
	}
Creates an DOM document from the given strings.
@param {object} assert the assertions
@param {string[]} aContent the content
@returns {Element} the DOM document's root element