Split FallbackActivityControllerHelper for Go

This splits FallbackActivityControllerHelper for Go and non-Go depending
on the underlying recents implementation. We also introduce a
GoActivityControllerHelper implementation as a base class to share the
stubbed methods for the Go ActivityControlHelper implementations.

Bug: 114136250
Test: Manual test NexusLauncher, l3GoWithIconRecents
Change-Id: I8a061bb83a851dd1d9988af17194f3e4aed24bb0