Move app => overview anim out of OverviewCommandHelper

This moves the core animation provider logic out of
OverviewCommandHelper to a separate class to divide out the class
responsibilities a little more and make it easier to override only the
animation logic in the future.

Bug: 114136250
Test: Manual test Launcher3QuickStepGo and NexusLauncher
Change-Id: I803431f9312eb1dca1233848f63a4be1b04469ef
2 files changed