Explicitly get Profile Owner

Continue refactoring work on the DevicePolicyManagerService,
explicitly getting the profile owner or device owner based
on the caller identity.

Bug: 163028934
Test: atest FrameworksServicesTests:DevicePolicyManagerTest
Test: atest com.android.cts.devicepolicy.MixedDeviceOwnerTest  com.android.cts.devicepolicy.MixedProfileOwnerTest
Change-Id: I85d2dc6f139181bf929c58182936a983d4dae94c
1 file changed