NotificationsFragment: always show appbar, even if there is no notifications

Thus, if user accidentally will filter everything, they will be able to return to initial state.

app/src/main/java/com/keylesspalace/tusky/fragment/NotificationsFragment.java

@@ -284,7 +284,7 @@ public class NotificationsFragment extends SFragment implements
     private void updateFilterVisibility() {
         CoordinatorLayout.LayoutParams params =
                 (CoordinatorLayout.LayoutParams) swipeRefreshLayout.getLayoutParams();
-        if (showNotificationsFilter && !showingError && !notifications.isEmpty()) {
+        if (showNotificationsFilter && !showingError) {
             appBarOptions.setExpanded(true, false);
             appBarOptions.setVisibility(View.VISIBLE);
             //Set content behaviour to hide filter on scroll