hotkeys without right mouse click sometimes cause position movement

Using Hotkeys(w,a,s,d) without holding right mouse click should not move position in sceneview. This is was captured by a test that was identified as instability a while ago but wasn't properly pinpointed as the position changes was minor. To produce, either 

1. enable and run test for example in [Internal link] or 
2. open a unity 3d project, add new tab -> scene, select camera and try hotkeys without holding right mouse click.

Reproducible on Mac