Fix NullPointerException in NetworkProviderSettings

- Avoid calling subfunctions when getView returns null

Bug: 301878710
Test: unit test
Change-Id: I8511ded693475468f6dda1d16d040c623097e997

src/com/android/settings/network/NetworkProviderSettings.java

@@ -190,7 +190,10 @@ public class NetworkProviderSettings extends RestrictedSettingsFragment
     @VisibleForTesting
     final Runnable mUpdateWifiEntryPreferencesRunnable = () -> {
         updateWifiEntryPreferences();
-        getView().postDelayed(mRemoveLoadingRunnable, 10);
+        View view = getView();
+        if (view != null) {
+            view.postDelayed(mRemoveLoadingRunnable, 10);
+        }
     };
     @VisibleForTesting
     final Runnable mHideProgressBarRunnable = () -> {