Resolve omnient to full-screen windowing mode

When multiple desktops is enabled, root organizer task is always in
freeform. Freeform bounds resolved in any launch params will be always
set via LaunchParamsController#layoutTask.

If currently in multi-desk mode, task launching in full-screen should
return early so no freeform bounds are resolved and set.

Flag: com.android.window.flags.enable_multiple_desktops_backend
Flag: com.android.window.flags.enable_freeform_display_launch_params
Fix: 410554758
Test: atest DesktopModeLaunchParamsModifierTests
      Manual test b/400983021 b/371220641
Change-Id: Ib48752887e7dfd685135c1e0b0e96cd6186708b2