
When the user clicks on "View Source" or "Web Page" in the "Extensions" tab of looking glass, the callback _onViewSource() or _onWebPage() is called and they try to close looking glass: this._lookingGlass.close(); But it does not work and generate the exception "this._lookingGlass is undefined". This patch fixes that. https://bugzilla.gnome.org/show_bug.cgi?id=693814