Don't silently fail when server unreachable

www/assets/js/rates.js

@@ -77,11 +77,15 @@ function getRates() {
             },
             function (xhr) {
                 app.dialog.close();
-                var error = $.parseJSON(xhr.responseText);
-                if (error && typeof error.msg != 'undefined') {
-                    app.dialog.alert(error.msg, "Error");
-                } else {
-                    app.dialog.alert("A server or network error occurred.", "Error");
+                try {
+                    var error = $.parseJSON(xhr.responseText);
+                    if (error && typeof error.msg != 'undefined') {
+                        app.dialog.alert(error.msg, "Error");
+                    } else {
+                        app.dialog.alert("There's a server or network problem. Check your Internet connection or try again later.", "Error");
+                    }
+                } catch (ex) {
+                    app.dialog.alert("There's a server or network problem. Check your Internet connection or try again later.", "Error");
                 }
             }, "GET");
 }

www/assets/js/track.js

@@ -111,11 +111,15 @@ function trackOpenAsync(routeTo, routeFrom, resolve, reject) {
             },
             function (xhr) {
                 app.dialog.close();
-                var error = $.parseJSON(xhr.responseText);
-                if (error && typeof error.msg != 'undefined') {
-                    app.dialog.alert(error.msg, "Error");
-                } else {
-                    app.dialog.alert("A server or network error occurred.", "Error");
+                try {
+                    var error = $.parseJSON(xhr.responseText);
+                    if (error && typeof error.msg != 'undefined') {
+                        app.dialog.alert(error.msg, "Error");
+                    } else {
+                        app.dialog.alert("There's a server or network problem. Check your Internet connection or try again later.", "Error");
+                    }
+                } catch (ex) {
+                    app.dialog.alert("There's a server or network problem. Check your Internet connection or try again later.", "Error");
                 }
                 reject();
             }, "GET");