Settings search - Navigate user to exact page

- remove duplicate index preference
- default set searchable = false when the preference has fragment
- make some fragments indexable

Bug: 143057584
Test: robotest & manual

Change-Id: I4d64f6106d2f92f0a45e8c7e26388677f593f412

src/com/android/settings/security/LockscreenDashboardFragment.java

@@ -57,9 +57,6 @@ public class LockscreenDashboardFragment extends DashboardFragment
     @VisibleForTesting
     static final String KEY_LOCK_SCREEN_NOTIFICATON_WORK_PROFILE =
             "security_setting_lock_screen_notif_work";
-    @VisibleForTesting
-    static final String KEY_ADD_USER_FROM_LOCK_SCREEN =
-            "security_lockscreen_add_users_when_locked";
 
 
     private AmbientDisplayConfiguration mConfig;
@@ -141,13 +138,6 @@ public class LockscreenDashboardFragment extends DashboardFragment
                     return controllers;
                 }
 
-                @Override
-                public List<String> getNonIndexableKeys(Context context) {
-                    final List<String> niks = super.getNonIndexableKeys(context);
-                    niks.add(KEY_ADD_USER_FROM_LOCK_SCREEN);
-                    return niks;
-                }
-
                 @Override
                 protected boolean isPageSearchEnabled(Context context) {
                     return new LockScreenPreferenceController(context, "anykey")