Steps to reproduce:
1. Open the attached project
2. Open the Assets/Scenes/MainScene.unity scene
3. Play the scene (when Mixed Reality Portal is on and simulations is on)
4. Switch to InterationManagerPollingInput by pressing the "Space" inside the Editor
5. Minimize the Editor while playing a scene
6. Go back to the Editor, observe the assertion in Console Window

Actual results: Assertion is thrown
Expected results: Unity should not throw the assertion

Note:
Make sure you are running Windows 10 build 16257 or higher

Reproduced with: 2017.2.0b11, 2017.2.0f3, 2017.3.0b3
Not reproduced with: 2017.2.0b10
Regression introduced in: 2017.2.0b11