Fixing multi-window task sizes in Recents activity

> In recents activity, getting the DeviceProfile size from the
root view, instead of the Display (as recents activtiy can be resized)
> The task size in Recents activity is now proportional to the activity
size instead of 50% screen size

Bug: 77875376
Change-Id: Ib417c31fc7ec8569876368134ef021452d60aa12
6 files changed