Explicitly set SetFlagsRule with NULL_DEFAULT

The default behavior of SetFlagsRule has been changed to DEVICE_DEFAULT which will load the default value from the device. These two tests requires to use the previous default behavior. Explicitly set the default behavior as NULL_DEFAULT.

Test: atest FrameworksMockingServicesTests:com.android.server.app.GameManagerServiceTests FrameworksCoreTestsRavenwood
Bug: 319266584
Bug: 319262520
Change-Id: I871f9572da556f6c4feb84b6ce85f8c533e2bdd0
2 files changed