Do not apply password quality to the parent

Prevent password quality set by the admin from applying on the primary
user, if targeting Android S and above:
* If the DPC calls setPasswordQuality on the parent profile DPM
  instance, throw.
* If the DPC calls setPasswordQuality on the regular DPM instance,
  simply ignore it on the primary profile.

This is guarded by the ChangeCompat framework.

Note about testing: As it proved difficult to mock/fake the
compatibility testing framework, the check is done via the injector,
which can be easily overridden.

Bug: 165573442
Test: atest com.android.cts.devicepolicy.MixedManagedProfileOwnerTest#testResetPasswordWithToken com.android.cts.devicepolicy.MixedManagedProfileOwnerTest#testGetPasswordExpiration FrameworksServicesTests:DevicePolicyManagerTest ManagedProfileTest
Test: atest FrameworksServicesTests:DevicePolicyManagerTest
Change-Id: I59354066dafb02fe1d464fd1ddabf3969a4d0f1b