Log focused tasks when skipping display change

When skipping moving a desktop task to the next display because
the target display has focused non-desktop tasks, log the names
of those tasks to aid in debugging.

Test: DesktopTasksControllerTest
Test: WMShellSmokeTestsDesktopMode
Flag: com.android.window.flags.enable_move_to_next_display_shortcut
Change-Id: Ia1e3089c43a2c900e4b85affa2e95b9506e61e9e