Use screen-based coordinates for AE interactive divider.

Without this, the velocity tracker may calculate unexpected velocity directions (example: http://shortn/_yDEnW9lAgp). Also snap to min/maxPosition when above the MIN_FLING_VELOCITY threshold to be consistent with the system split screen: http://shortn/_nbar2leR9v.

Flag: None - subfeature of unreleased feature
Bug: 343235405
Test: atest DividerPresenterTest
Change-Id: I6f063dcd8dfd63665d6b19679aa1240d5a6c7c88