overhauled button pressed backStack behaviour...use a JS callback to let it work with JS calls

code/panes.js

@@ -2,6 +2,9 @@
 //
 window.show = function(id) {
         window.hideall();
+        if (typeof android !== 'undefined' && android && android.switchToPane) {
+          android.switchToPane(id);
+        }
         switch(id) {
                 case 'full':
                         window.chat.show('full');

code/smartphone.js

@@ -91,11 +91,7 @@ window.runOnSmartphonesAfterBoot = function() {
       // this is a hack, accessing Leaflet’s private _container is evil
       $(this._container).on('taphold', function() {
         window.renderPortalDetails(guid);
-        if (typeof android !== 'undefined' && android && android.portalLongPressed) {
-          android.portalLongPressed();
-        } else {
-            window.smartphone.sideButton.click();
-        }
+        window.show('info');
       });
     });
   });