implement Service.onTimeout() in FetchForegroundService

src/main/java/org/thoughtcrime/securesms/service/FetchForegroundService.java

@@ -108,4 +108,15 @@ public final class FetchForegroundService extends Service {
   public IBinder onBind(Intent intent) {
     return null;
   }
+
+  @Override
+  public void onTimeout(int startId, int fgsType) {
+    if (fetchingSynchronously) {
+      fetchingSynchronously = false;
+      synchronized (STOP_NOTIFIER) {
+        STOP_NOTIFIER.notifyAll();
+      }
+    }
+  }
+
 }