When the application page is loaded via https, google stuff needs also be loaded from https, otherwise the browsers won't load it because of mixed content prohibition.
Please change the line in loadScripts to
Loader.defaultUrl = location.protocol.replace('file', 'https')+'//maps.google.com/maps/api/js?';
and the line in markerclusterer to
MarkerClusterer.IMAGE_PATH = location.protocol.replace('file', 'https')+"//google-maps-utility-library-v3.googlecode.com/svn/trunk/markerclustererplus/images/m";
When the application page is loaded via https, google stuff needs also be loaded from https, otherwise the browsers won't load it because of mixed content prohibition.
Please change the line in loadScripts to Loader.defaultUrl = location.protocol.replace('file', 'https')+'//maps.google.com/maps/api/js?'; and the line in markerclusterer to MarkerClusterer.IMAGE_PATH = location.protocol.replace('file', 'https')+"//google-maps-utility-library-v3.googlecode.com/svn/trunk/markerclustererplus/images/m";