Mark IME as a core app

Bug: 5233488
Change-Id: I58e05ee1187d4f32450037cb088129d1deec58b4
diff --git a/java/AndroidManifest.xml b/java/AndroidManifest.xml
index 703258b..2baae54 100644
--- a/java/AndroidManifest.xml
+++ b/java/AndroidManifest.xml
@@ -1,4 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+        coreApp="true"
         package="com.android.inputmethod.latin">
 
     <uses-permission android:name="android.permission.VIBRATE"/>