How to reproduce:
1. Open QA-supplied project
2. Make sure that "Scripting Runtime Version" setting is set to Stable(.NET 3.5 Equivalent) (Player settings -> Other settings)
2. Load "TEST" scene
3. Enter the Play mode, open Console window and observe
4. Now set "Scripting Runtime Version" setting to Experimental(.NET 4.6 Equivalent) (Player settings -> Other settings)
5. Enter Playmode, open Console window and observe

Expected result: File separators should be the same using both versions of .NET runtime.
Actual result: File separators differ from slash to backslash using different versions of .NET runtime.

Reproducible with: 2017.2.0b1, 2017.2.0a3, 2017.1.0f3, 2017.1.0a6
Not reproducible with: 2017.3.0a2, 2017.2.0b5, 2017.2.0b3, 2017.2.0b2 (+ 2017.1.0a5 or lower due to "Scripting Runtime Version" setting not being introduced yet)