Implement fallback recents activity for Go

Implement recents activity for Go for when the default launcher does not
have recents implemented. To do this, we factor out some common recents
activity functionality from RecentsActivity and extend it to make a Go
specific activity that pops in the icon recents fragment.

Bug: 114136250
Test: Manual test NexusLauncher and Launcher3QuickstepGo by installing a
quickstep-less launcher and setting it to default
Change-Id: I936568489e8966da4a62e4b779ae660a220f2aeb