[Fill Dialog Improvements] Deprecate API's

Deperecate API's that are no longer relevant.

Bug: 336223371
Bug: 377868687
Flag: android.service.autofill.fill_dialog_improvements
Test: atest CtsAutoFillServiceTestCases
Change-Id: I371e299c2980ac525de5e6c3f9c4e2cf63bae5b5
diff --git a/services/autofill/features.aconfig b/services/autofill/features.aconfig
index 1dc3b73..bd46deb 100644
--- a/services/autofill/features.aconfig
+++ b/services/autofill/features.aconfig
@@ -22,3 +22,11 @@
     description: "Guards against Autofill-Credman Phase1 developer integration via new APIs"
     bug: "320730001"
 }
+
+flag {
+    name: "fill_dialog_improvements"
+    is_exported: true
+    namespace: "autofill"
+    description: "Improvements for Fill Dialog, including deprecation of pre-trigger API's"
+    bug: "336223371"
+}