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/deletionhelper/AutomaticStorageManagerSettings.java

@@ -163,7 +163,7 @@ public class AutomaticStorageManagerSettings extends DashboardFragment
 
     /** For Search. */
     public static final BaseSearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
-            new BaseSearchIndexProvider() {
+            new BaseSearchIndexProvider(R.xml.automatic_storage_management_settings) {
                 @Override
                 protected boolean isPageSearchEnabled(Context context) {
                     return false;