Add concept of Flag values under window object to ensure values are

parsed before use

ui/src/index.tsx

@@ -4,10 +4,13 @@ import CssBaseline from "@material-ui/core/CssBaseline";
 import { Provider } from "react-redux";
 import App from "./App";
 import store from "./store";
+import parseFlagsUnderWindow from "./parseFlags";
 import * as serviceWorker from "./serviceWorker";
 import { saveState } from "./localStorage";
 import { SettingsState } from "./reducers/settingsReducer";
 
+parseFlagsUnderWindow();
+
 let currentSettings: SettingsState | undefined = undefined;
 store.subscribe(() => {
   const prevSettings = currentSettings;