Add convenience dialog_button() JS function

tailbone/static/js/tailbone.js

@@ -68,6 +68,24 @@ function get_uuid(obj) {
 }
 
 
+/*
+ * Return a jQuery object containing a button from a dialog.  This is a
+ * convenience function to help with browser differences.  It is assumed
+ * that it is being called from within the relevant button click handler.
+ * @param {event} event - Click event object.
+ */
+function dialog_button(event) {
+    var button = $(event.target);
+
+    // TODO: not sure why this workaround is needed for Chrome..?
+    if (! button.hasClass('ui-button')) {
+        button = button.parents('.ui-button:first');
+    }
+
+    return button;
+}
+
+
 /*
  * reference to existing timeout warning dialog, if any
  */