Fix adaptive brightness not appearing in Settings search

Change-Id: I33ed525b3c051a982869114754bd3b7423b61d22
Fixes: 117449384
Test: manual

res/xml/display_settings.xml

@@ -44,7 +44,6 @@
         android:title="@string/auto_brightness_title"
         android:summary="@string/summary_placeholder"
         android:fragment="com.android.settings.display.AutoBrightnessSettings"
-        settings:searchable="false"
         settings:controller="com.android.settings.display.AutoBrightnessPreferenceController" />
 
     <com.android.settingslib.RestrictedPreference

src/com/android/settings/display/AutoBrightnessPreferenceController.java

@@ -52,7 +52,7 @@ public class AutoBrightnessPreferenceController extends TogglePreferenceControll
     public int getAvailabilityStatus() {
         return mContext.getResources().getBoolean(
                 com.android.internal.R.bool.config_automatic_brightness_available)
-                ? AVAILABLE_UNSEARCHABLE
+                ? AVAILABLE
                 : UNSUPPORTED_ON_DEVICE;
     }