Check to see if FCM is available at app launch.

app/src/main/java/org/thoughtcrime/securesms/ApplicationContext.java

@@ -44,6 +44,7 @@
 import org.thoughtcrime.securesms.jobs.FcmRefreshJob;
 import org.thoughtcrime.securesms.jobs.MultiDeviceContactUpdateJob;
 import org.thoughtcrime.securesms.jobs.PushNotificationReceiveJob;
+import org.thoughtcrime.securesms.jobs.RefreshAttributesJob;
 import org.thoughtcrime.securesms.jobs.RefreshPreKeysJob;
 import org.thoughtcrime.securesms.logging.AndroidLogger;
 import org.thoughtcrime.securesms.logging.CustomSignalProtocolLogger;
@@ -67,6 +68,7 @@
 import org.thoughtcrime.securesms.service.UpdateApkRefreshListener;
 import org.thoughtcrime.securesms.storage.StorageSyncHelper;
 import org.thoughtcrime.securesms.util.FeatureFlags;
+import org.thoughtcrime.securesms.util.PlayServicesUtil;
 import org.thoughtcrime.securesms.util.TextSecurePreferences;
 import org.thoughtcrime.securesms.util.concurrent.SignalExecutors;
 import org.thoughtcrime.securesms.util.dynamiclanguage.DynamicLanguageContextWrapper;
@@ -127,6 +129,7 @@ public void onCreate() {
     initializePendingMessages();
     initializeBlobProvider();
     initializeCleanup();
+    initializePlayServicesCheck();
 
     FeatureFlags.init();
     NotificationChannels.create(this);
@@ -375,6 +378,21 @@ private void initializeCleanup() {
     });
   }
 
+  private void initializePlayServicesCheck() {
+    if (TextSecurePreferences.isFcmDisabled(this)) {
+      PlayServicesUtil.PlayServicesStatus status = PlayServicesUtil.getPlayServicesStatus(this);
+
+      if (status == PlayServicesUtil.PlayServicesStatus.SUCCESS) {
+        Log.i(TAG, "Play Services are newly-available. Updating to use FCM.");
+
+        TextSecurePreferences.setFcmDisabled(this, false);
+        ApplicationDependencies.getJobManager().startChain(new FcmRefreshJob())
+                                               .then(new RefreshAttributesJob())
+                                               .enqueue();
+      }
+    }
+  }
+
   @Override
   protected void attachBaseContext(Context base) {
     super.attachBaseContext(DynamicLanguageContextWrapper.updateContext(base, TextSecurePreferences.getLanguage(base)));