MouseArea: Fix cancelling the double click when the windows loses focus

Without this, the next click is not received after the windows loses 
focus while we double clicked but not released the mouse.

This may happen if the onDoubleClicked opens a new window

Change-Id: I86742de2bb1ea4c9657b9d5e90472d093293177d
Reviewed-by: Alan Alpert <aalpert@blackberry.com>