System apps must target API 28 or higher

Bug: 120997004
Change-Id: I998a443a4327c47cbab8e4bc4843be1693f05d8d
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 4ac51ab..1a485ed 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -20,7 +20,7 @@
 <manifest
     xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.android.launcher3">
-    <uses-sdk android:targetSdkVersion="23" android:minSdkVersion="21"/>
+    <uses-sdk android:targetSdkVersion="28" android:minSdkVersion="21"/>
     <!--
     Manifest entries specific to Launcher3. This is merged with AndroidManifest-common.xml.
     Refer comments around specific entries on how to extend individual components.