Create AConfig flag to guard bug fix for AssistStructure.

Bug: 369503426
Change-Id: Ia832dd5bcf260f40217e9412ff96a130c690fabe
Test: presubmit
Flag: android.app.assist.flags.add_placeholder_view_for_null_child
diff --git a/AconfigFlags.bp b/AconfigFlags.bp
index a0f38d9..a5452e7 100644
--- a/AconfigFlags.bp
+++ b/AconfigFlags.bp
@@ -23,6 +23,7 @@
         "android-sdk-flags-java",
         "android.adaptiveauth.flags-aconfig-java",
         "android.app.appfunctions.flags-aconfig-java",
+        "android.app.assist.flags-aconfig-java",
         "android.app.contextualsearch.flags-aconfig-java",
         "android.app.flags-aconfig-java",
         "android.app.jank.flags-aconfig-java",
@@ -1229,6 +1230,20 @@
     defaults: ["framework-minus-apex-aconfig-java-defaults"],
 }
 
+// Assist
+aconfig_declarations {
+    name: "android.app.assist.flags-aconfig",
+    package: "android.app.assist.flags",
+    container: "system",
+    srcs: ["core/java/android/app/assist/flags.aconfig"],
+}
+
+java_aconfig_library {
+    name: "android.app.assist.flags-aconfig-java",
+    aconfig_declarations: "android.app.assist.flags-aconfig",
+    defaults: ["framework-minus-apex-aconfig-java-defaults"],
+}
+
 // Smartspace
 aconfig_declarations {
     name: "android.app.smartspace.flags-aconfig",