Recalculate real caller if caller results in block

When the caller==realcaller while sending an own PendingIntent (which
should be avoided, but it happens) and the caller does not allow the PI
start, calculate if the real caller is allowed (which is possible,
because for a PI the callerApp is null and the realCallerApp is
calculated).

Test: atest CtsPackageManagerTestCases:android.content.pm.cts.PackageManagerTest#testGetLaunchIntentSenderForPackage  ConnectivityCoverageTests:android.net.connectivity.com.android.server.connectivity.NetworkNotificationManagerTest#testNotifyNoInternet_asDialog
Fixes: 307911244
Fixes: 307907820
Fixes: 308163300
Change-Id: I9cd0d5022c6302a2a802749f009f6f2372f8bb01