[CS] Have classes call ScreenPinningRequest directly, not through CS.

Bug: 277764509
Test: pin app -> verify screen pinning request UI is shown correctly
Test: pin app then rotate screen -> verify screen pinning request UI is
redrawn due to config change
Test: atest OverviewProxyServiceTest CentralSurfacesImplTest

Change-Id: Ieddd799652989457ca1029f91fab451f8f76fe5c
10 files changed