How to reproduce:
1. Open the attached "AssertionRepro" project
2. Go to "Scenes" folder and open "Levels" scene, enter playmode
3. Null Reference Exception error will appear in the console, double click on it to open the script that causes the error (make sure that Visual Studio would not be open before doing this)

Expected result: Script gets opened, no errors appear
Actual result: Script gets opened, "Assertion failed: Assertion failed on expression: 'm_currentEntriesPtr != NULL && m_IsGetingEntries'" assertion appears

Regression introduced in - 2017.3.0a1
Reproducible with - 2018.1.0b1, 2017.3.0p1, 2017.3.0a1
Not reproducible with - 2017.2.1p1

Notes:
1. Happens with Visual Studio 2017/2015, does not happen with Visual Studio Code or MonoDevelop
2. Assertions are thrown only when opening script by double clicking on the error, opening a script trough a Project window, does not seem to cause the assertions