Add config to change drag-to-top-edge behavior

This CL adds a config to change the consequence of the drag-to-top-edge
action from fullscreen’ed to maximized.

Bug: 376351166
Flag: com.android.window.flags.enable_drag_to_maximize
Test: DesktopTasksControllerTest
Change-Id: I98e13e0a7b8dba6a75a0ffd044fcb5b7b22a8eb4
5 files changed