Update cancel device state request to require foreground for cts compat

Previous change in ag/28368952 made the requirements to cancel
a device state request too open, which caused cts compat issues.
This change reduces the ability to cancel a state request, to
requiring that a process is in the foreground while not being
required to be the top app. This allows a process in Picture in
Picture to be able to cancel the state request.

Test: DeviceStateManagerTests
Test: ExtensionRearDisplayPresentationTest
Bug: 358004667
Flag: android.hardware.devicestate.feature.flags.device_state_requester_cancel_state
Change-Id: I435a2f6b2910abd54e85c3bc0a5424deee67d67a