Add init_user0 command.

Change-Id: Icf746ec1968a073fde707ecc788b648f5803fd38
diff --git a/Ext4Crypt.h b/Ext4Crypt.h
index 3fb6f16..9005f4a 100644
--- a/Ext4Crypt.h
+++ b/Ext4Crypt.h
@@ -36,6 +36,7 @@
 int e4crypt_set_field(const char* path, const char* fieldname,
                       const char* value);
 
+int e4crypt_init_user0();
 int e4crypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral);
 int e4crypt_destroy_user_key(userid_t user_id);