Split DevicePolicySafetyCheckerIntegrationTester in 3 tests.

That test had too many logic and was actually testing 3 different
APIs:

- Whether (all) the operations are safe / unsafe
- The exception reason
- The isOperationSafe() API

This CL split those checks in 3 different tests, which makes it
easier to maintain them.

NOTE: the ProfileOwnerTests are failing due to permissions, but
that's unrelated to this change - they're failing without it as
well.

Test: atest CtsDevicePolicyManagerTestCases:DeviceOwnerTest#testDevicePolicySafetyCheckerIntegration_allOperations,testDevicePolicySafetyCheckerIntegration_isSafeOperation,testDevicePolicySafetyCheckerIntegration_unsafeStateException \
Test: atest CtsDevicePolicyManagerTestCases:ProfileOwnerTest#testDevicePolicySafetyCheckerIntegration_allOperations,testDevicePolicySafetyCheckerIntegration_isSafeOperation,testDevicePolicySafetyCheckerIntegration_unsafeStateException

Bug: 172376923
Bug: 180655054

Change-Id: Ife936cea89c6e21a56454766ecb4b29b652bd584