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/inputmethod/SpellCheckersSettings.java

@@ -37,9 +37,15 @@ import androidx.preference.PreferenceScreen;
 import com.android.settings.R;
 import com.android.settings.SettingsActivity;
 import com.android.settings.SettingsPreferenceFragment;
+import com.android.settings.search.BaseSearchIndexProvider;
 import com.android.settings.widget.SwitchBar;
 import com.android.settings.widget.SwitchBar.OnSwitchChangeListener;
+import com.android.settingslib.search.SearchIndexable;
 
+/**
+ * Settings screen for spell checker
+ */
+@SearchIndexable
 public class SpellCheckersSettings extends SettingsPreferenceFragment
         implements OnSwitchChangeListener, OnPreferenceClickListener, OnPreferenceChangeListener {
     private static final String TAG = SpellCheckersSettings.class.getSimpleName();
@@ -274,4 +280,7 @@ public class SpellCheckersSettings extends SettingsPreferenceFragment
         }
         updatePreferenceScreen();
     }
+
+    public static final BaseSearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
+            new BaseSearchIndexProvider(R.xml.spellchecker_prefs);
 }