CrOS Media App: Remove `window.features` in favour of using loadTimeData

This was racey, we don't need this anymore after cl/343193875 lands
and ships in our CIPD build.

DO_NOT_SUBMIT until after cl/343193875 lands in chromium.

Bug: b/172985712
Change-Id: I8b24f132e9bf853a67974bd15bb32716d56ec47e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2549201Reviewed-by: David Lei <dlei@google.com>
Reviewed-by: Bugs Nash <bugsnash@chromium.org>
Commit-Queue: David Lei <dlei@google.com>
Cr-Commit-Position: refs/heads/master@{#830068}

chromeos/components/media_app_ui/media_app_guest_ui.cc

@@ -47,6 +47,7 @@ content::WebUIDataSource* CreateMediaAppUntrustedDataSource(
                             kChromeosMediaAppBundleResources[i].value);
   }
 
+  // Note: go/bbsrc/flags.ts processes this.
   delegate->PopulateLoadTimeData(source);
   source->UseStringsJs();
 

chromeos/components/media_app_ui/resources/js/receiver.js

@@ -299,15 +299,6 @@ function mutationCallback(mutationsList, observer) {
 }
 
 window.addEventListener('DOMContentLoaded', () => {
-  // TODO(crbug/1138798): Reorder .js deps so this can be done at load time.
-  // Note: go/bbsrc/flags.ts processes this, `window.features` variable.
-  /** @type{{features: Object<string, boolean>}} */ (window).features = {
-    imageAnnotation: loadTimeData.getBoolean('imageAnnotation'),
-    pdfInInk: loadTimeData.getBoolean('pdfInInk'),
-    flagsMenu: loadTimeData.getBoolean('flagsMenu'),
-    isDevChannel: loadTimeData.getBoolean('isDevChannel'),
-  };
-
   const app = getApp();
   if (app) {
     initializeApp(app);