Implement new handle menu UI

Updates the handle menu to the newest spec. The menu is now divided
into three floating windows so three windowless windows associated
with the window decoration are created.

Menu in proto 2 (fullscreen):
https://screenshot.googleplex.com/4KGBDtRZ9mRedTS.png
Menu in proto 2 (desktop):
https://screenshot.googleplex.com/5DhrrPavNSSKrbH.png
Menu in proto 1: https://screenshot.googleplex.com/6GyUqpJGKdPt2MX.png

Bug: 274630524
Test: proto1/proto2 - open handle menu, see new UI, test buttons
still work

Change-Id: I9157ec0223cd1077dd3ae24cb39e535289775557