Now that `GroupedTaskInfo` propagates the `deskId` from
Shell (see ag/31825217), we need to plumb this value in
Launcher through `DesktopTask`.
Future CLs will use this value in Overview.
Bug: 395911284
Test: m, modified existing tests.
Flag: com.android.window.flags.enable_multiple_desktops_frontend
Flag: com.android.window.flags.enable_multiple_desktops_backend
Change-Id: I396250e0cac761c4c5f7e8b2d6cddbe68e646217
Ahmed Fakhry
dafc2d4c42