CMFileManager: Fix problem when "Use swipe gestures" on

When "Use swipe gestures" is on, click on listview item has no
effects.
Since ev.getX() or ev.getY() is returning floating point, while
the previous touch location is stored as fixed point. When
there is fractional parts in getX(), it will always return
false when it compares to the previous touch point, making the flinger
logic to think the touch does moved while it is actually not.

FEIJ-290

Change-Id: Ib208b6115c0758facf29461ef45f6ffd5c67adce