Add API surface for "keep SMS app running".

Bug: 109809543
Test: build & boot
Change-Id: Ie9ebf1f34052394a92c3f260413c18596709d3a3
diff --git a/Android.bp b/Android.bp
index a603006..c349d88 100644
--- a/Android.bp
+++ b/Android.bp
@@ -77,6 +77,7 @@
         "core/java/android/app/ISearchManager.aidl",
         "core/java/android/app/ISearchManagerCallback.aidl",
         "core/java/android/app/IServiceConnection.aidl",
+        "core/java/android/app/ISmsAppService.aidl",
         "core/java/android/app/IStopUserCallback.aidl",
         "core/java/android/app/job/IJobCallback.aidl",
         "core/java/android/app/job/IJobScheduler.aidl",