使用android：sharedUserId =“ android.uid.system”更新已安装的系统应用

Question

I'm developing system app for android. So, the app on phone now is system, phone haven't root.

I need to silent install apps from this app, but i read that i need to this in manifest

    android:sharedUserId="android.uid.system"

But when i'm trying to update app it's stops, and in Logs i see this :

W/PackageManager: Package "packagename" tried to change user null

I/ActivityManager: Force stopping "packagename" appid=10022 user=-1: installPackageLI