Reland "Move focused task to front when attaching RecentsView"

This reland commit 86ac825061d48d169998485f419208e851ee402c

- When removing focused task, don't add it to taskpool as we'll immediately re-add the task

Bug: 192471181
Test: NexusLauncherTests
Change-Id: If4a9de74ac63ac14cf6a99262db31cb9f31b987e
3 files changed