Removed redundant printout for "OnMouseMove called without moving the mouse"

Removed redundant printout for "OnMouseMove called without moving the mouse"

This fixes #416.
The problem with this printout (as explained in the issue) is that on
Windows (at least for specific devices/OS) GetMouseMovePointsEx can
return duplicate points, so it’s either adding a check in the Windows
layer or remove the printout. Adding a check in the Windows layer looks
redundant though, as this is already checked in NativeWindowBase, so
removing the printout looks preferable.