When the sharedUserSetting of the application on /system is different from the...

When the sharedUserSetting of the application on /system is different from the sharedUserSetting on /data, we should trust the sharedUserSetting on /system

A new system app appeared by OTA, but we already had a non-system one of the same name installed earlier, if the the sharedUserSetting of the application on /system is different from
the sharedUserSetting on /data, and the version on system is smaller than the version on /data, the OTA upgrade will fail.

Bug: 272714709

Test: Manual.
Test: 1] installed an application A on /data
Test: 2] in OTA target package preload an application B on /system.
         which has the same package name and signature with A,
         but the sharedUserSetting of the application on /system
         is different from the sharedUserSetting on /data
Test: 3] OTA upgrade
Change-Id: I21b0c24ae363ff6be06dcd0f187273200b2991a6