Support nav fade anim for the case of swiping left/right to a new task

The ReorderMode of the swiping left/right to a new task is
REORDER_MOVE_TO_ORIGINAL_POSITION which is the same as the case swiping
up and then down to back to the original task.

Add a new flag to distinguish between these two cases.

Bug: 187783109
Test: atest RecentsAnimationControllerTests

Change-Id: I0bd1005b23041459286fcd7f6488b09b43ef3867