Add DeviceConfig namespace for AppSearch

Adds a new namespace to DeviceConfig for features
relating to AppSearch.

Bug: 173532925
Test: build
Change-Id: I5887899d9292bf88ea5007d94c20b8690ee73872
diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 1b3edcf..fe70eaf 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -8919,6 +8919,7 @@
     method @RequiresPermission(android.Manifest.permission.WRITE_DEVICE_CONFIG) public static boolean setProperty(@NonNull String, @NonNull String, @Nullable String, boolean);
     field public static final String NAMESPACE_ACTIVITY_MANAGER = "activity_manager";
     field public static final String NAMESPACE_ACTIVITY_MANAGER_NATIVE_BOOT = "activity_manager_native_boot";
+    field public static final String NAMESPACE_APPSEARCH = "appsearch";
     field public static final String NAMESPACE_APP_COMPAT = "app_compat";
     field public static final String NAMESPACE_APP_HIBERNATION = "app_hibernation";
     field public static final String NAMESPACE_ATTENTION_MANAGER_SERVICE = "attention_manager_service";
diff --git a/core/java/android/provider/DeviceConfig.java b/core/java/android/provider/DeviceConfig.java
index 7e40497..31cf63c 100644
--- a/core/java/android/provider/DeviceConfig.java
+++ b/core/java/android/provider/DeviceConfig.java
@@ -108,6 +108,13 @@
     public static final String NAMESPACE_APP_HIBERNATION = "app_hibernation";
 
     /**
+     * Namespace for all AppSearch related features.
+     * @hide
+     */
+    @SystemApi
+    public static final String NAMESPACE_APPSEARCH = "appsearch";
+
+    /**
      * Namespace for app standby configurations.
      *
      * @hide