Delegate PrintServicesLoader to the framework's one

1. Remove the duplicated PrintServicesLoader in Settings
2. Make a androidx.loader in Settings and internally just delegate all calls to the real PrintServicesLoader
3. Get the result from the real loader

Test: manual
Fixes: 111581651
Change-Id: I2a9b3653f5c68f8383a468cd16ef5f7c3fd4bc3a

src/com/android/settings/print/PrintSettingsFragment.java

@@ -168,7 +168,7 @@ public class PrintSettingsFragment extends ProfileSettingsPreferenceFragment
             PrintManager printManager =
                     (PrintManager) getContext().getSystemService(Context.PRINT_SERVICE);
             if (printManager != null) {
-                return new PrintServicesLoader(printManager, getContext(),
+                return new SettingsPrintServicesLoader(printManager, getContext(),
                         PrintManager.ALL_SERVICES);
             } else {
                 return null;