Add icon recents fragment for IconRecents

Split out overview_panel from recents and override it with IconRecents
version to replace the recents view entirely.

Currently, on the IconRecents build variant, as expected, this hits a
class cast exception since many quickstep classes assume the overview
panel is an instance of RecentsView. All other variants build and push
fine.

Bug: 114136250
Test: Build + push NexusLauncherDebug, Launcher3Go,
Launcher3GoQuickstep, Launcher3GoQuickstepIconRecents
Change-Id: I3ac7331772e53ee81cb1735a709b4fb7b3bdb78c