Pre-fixup for nav up button

- Remove SettingsDrawerActivity.EXTRA_SHOW_MENU and force up nav button
  to always show. The button doesn't do anything yet. It just finishes
  current activity.
- Remove dead code about suggestions

Change-Id: I61fa9fefbaa9bced841a05969544b1c824c564ce
Bug: 72337421
Test: rebuild

src/com/android/settings/deviceinfo/StorageSettings.java

@@ -236,7 +236,6 @@ public class StorageSettings extends SettingsPreferenceFragment implements Index
                 Intent intent = Utils.onBuildStartFragmentIntent(getActivity(),
                         StorageDashboardFragment.class.getName(), args, null,
                         R.string.storage_settings, null, false, getMetricsCategory());
-                intent.putExtra(SettingsDrawerActivity.EXTRA_SHOW_MENU, true);
                 getActivity().startActivity(intent);
                 finish();
             }