For now, shelve persistance across sessions

src/components/structures/MatrixChat.js

@@ -1313,7 +1313,10 @@ export default React.createClass({
             // TODO: Pass reason for failure as third argument to trackEvent
             Analytics.trackEvent('E2E', 'Decryption failure');
         });
-        dft.loadTrackedEventHashMap();
+
+        // Shelved for later date when we have time to think about persisting history of
+        // tracked events across sessions.
+        // dft.loadTrackedEventHashMap();
 
         const stopDft = dft.start();