Doze brightness for non-offloaded watchfaces

Enable auto-brightness in doze so that we can support top-of-minute updates.

Disable auto-brightness in doze temporarily if the offload session doesn't allow it - we don't want to use auto-brightness while the offload session is in control of the display.

Update the auto-brightness value in AutomaticBrightnessController when switching modes. This can be done in the same thread and there's no need to notify the listeners if the mode is switched from updatePowerState().

Use the display state and not the policy when setting auto-brightness state - this is reverting to the code we had before and in ag/26495348 we decided to rely on the state consistently.

Don't use the initial doze brightness based on last observed lux because of b/328714026.

Don't use the default doze brightness when auto-brightness enabled in doze - sometimes AutomaticBrightnessController might not provide a brightness value (when the lux isn't ready yet or the sensor is temporarily disabled). We don't want to cause unexpected brightness changes in those situations with the default doze brightness.

Test: adb logcat | grep -i "brightnessEvent"
Test: atest AutomaticBrightnessControllerTest
Test: atest AutomaticBrightnessStrategyTest
Test: atest BrightnessReasonTest
Test: atest DisplayPowerControllerTest
Test: atest DisplayOffloadSessionImplTest
Test: atest LocalDisplayAdapterTest
Bug: 327392714
Bug: 328714026
Change-Id: Ie3ae27e69d3edad41d27cc1f871295e8a73c09cb