Editor primitives render incorrectly in stereoscopic with instanced stereo

Trigger box icons move around when oculus head movement is used.

Found in //UE4/Release-Staging-4.13 @ 3090357
QA-Promotion map

Edit: 08-22: This affects volumes as well as their editor icons, updating.

1. Open QAGame and load the QA-Promotion level
2. Open Project Settings > Rendering: Enable Instanced Stereo
3. In the Level Editor Toolbar, dropdown the Play options and select "VR Preview"
4. Look at a trigger box and move your head left and right with the oculus

Result: Trigger box icons moves with the oculus

Expected Result: Trigger boxes dont move based on head movement