Desktop Windowing: Log task minimize reasons

Add minimize reason to the information logged when a desktop task goes
from visible to invisible.

Test: use atomviewer to ensure minimize reasons logged
Flag: com.android.window.flags.enable_desktop_windowing_task_limit
Bug: 358002042
Change-Id: I1411fb7a55cdb9b3908c20dd8d542faaa54a83a6