Make SettingsProvider device-aware

Allow system_server to override settings values for a
virtual device. Since virtual devices are ephemeral,
there is no need to persist settings specific to virtual
devices. Note that device-aware settings are applicable
only for secure and system settings, not for global,
config or ssaid settings. For more details, please refer
to go/device-aware-settings.

Test: atest SettingsProviderTest (module)
Test: atest android.provider.cts.settings.Settings_ConfigTest
Test: atest android.provider.cts.settings.Settings_SecureTest
Test: atest android.provider.cts.settings.Settings_SystemTest
Test: atest android.provider.cts.settings.SettingsTest
Test: atest android.provider.cts.settings.Settings_MemoryUsageTest
Test: atest android.appsecurity.cts.ReadableSettingsFieldsTest
Test: atest android.appsecurity.cts.SettingsProviderInvalidKeyTest
Flag: android.companion.virtualdevice.flags.device_aware_settings_override
Bug: 371801645
Change-Id: I3584ccb5911a8c44c2fbbfbfd4611b4e4331bb86