strange artifact in depthmap of a mirroring glass
Structured or not, light gets reflected and the sensor has no way of telling if the scene is imaged directly or by reflection.

To try and reduce the effect of reflections from the glass, you might want to use a polariser. Photographic polarising filters have lots of useful applications and one of them is reducing glare when you are trying to shoot artifacts within a museum glass case (for example). 

You can find really cheap polarising filters in the second-hand boxes in camera shops, or buy polarising sheets which you can cut into various shapes.

One thing that would be good to note however is that the camera may already be using a polarising element internally which might interfere with an additional polariser which will worsen the situation.

Hope this helps.