Upgrading app in background using Device Policy Controller

Question

I have a working DPC app which is the Device Owner. I have tried this on two different Android 6.0.1 devices to rule out any device/manufacturer issues.

I used

Answer 1

The error was coming from the following Android 6.0.1 code in frameworks/base/services/core/java/com/android/server/pm/PackageManagerService.java.

if ((pkg.applicationInfo.flags&ApplicationInfo.FLAG_TEST_ONLY) != 0) {
    if ((installFlags & PackageManager.INSTALL_ALLOW_TEST) == 0) {
        res.setError(INSTALL_FAILED_TEST_ONLY, "installPackageLI");
        return;
    }
}

I checked the app which I was trying to install, and found that the FLAG_TEST_ONLY bit was set. Why is Android Studio 3.0.0 setting FLAG_TEST_ONLY on APKs?