* current cursor position.
* @param {string} [button.imageId] `id` attribute of the button HTML element. Can be
* used to define the image with CSS if it's not provided as `imageFile`.
+ * @param {string} [speedTip]
+ * @param {string} [tagOpen]
+ * @param {string} [tagClose]
+ * @param {string} [sampleText]
+ * @param {string} [imageId]
*/
function insertButton( button, speedTip, tagOpen, tagClose, sampleText, imageId ) {
var $button;