[Install-unknown-apps] not include all the apps that have OP_REQUEST_INSTALL_PACKAGES granted

Due to a recent change in AppOpsService, apps that share system_uid have all the appops granted. However, we don't want them to be listed under "Install unknown apps" if they don't explicitly declare the permission usage of REQUEST_INSTALL_PACKAGES in their manifest. This CL fixes that.

Change-Id: I025bc17c335093ae5d3b15a3bef67d659c8f790f
BUG: 338066634
BUG: 336677341
FIXES: 338066634
Test: manual by checking the Settings page