Use power mode of all independent displays to control power optimisations.

In the following cases, if there is any performance-optimised/independent active display (powered on) then power optimisations are disabled. If there is no performance-optimised/independent active display then power optimisations are enabled, even if there are power-optimised displays that are powered on.
* Physical or virtual display power mode change
* Physical or virtual display added or removed

Power optimisations include:
* Lowering thread priority

Bug: 342681202
Bug: 241285876

Flag: android.companion.virtualdevice.flags.correct_virtual_display_power_state

Test: manually tested with flag on/off using Android Auto Projected

Change-Id: I96068c8779dbfe2b51b4d9acd522b6cb3995681f