To reproduce:

1. Open attached project.
2. Open script: Editor->StoreRestoreSceneSetup.cs
3. There is test, RUN_ME_AS_FAST_AS_POSSIBLE, add a comment, or add any letter to the existing comment to make it recompile.
4. Double click the same test to run in Test Runner upon EditMode tab (scroll down at the very bottom)(don't wait for recompilation).

Expected result: Tests runs fine.
Actual result: Test Runner gets stuck at some point and Running Tests dialog does not disappear:

NOTES:
Unity starts recompilation after receiving focus.
If waited after recompilation, everything starts working fine. Only occurs if clicked really fast.
Sometimes [OneTimeTearDown] does not get called after running test (you can tell that if after running a tests two scenes are left on hierarchy)
Most of the times, it executes [OneTimeTearDown], but Test Runner is still stuck and dialog does not disappear.
Running any test again fixes the stuck dialog.

The tests itself tests SceneManagerSetup functionality (opens two scenes, executes GetSceneManagerSetup (might be related))

Does not repro on other tests than this one
Does not repro on empty project (maybe recompilation time is too short)
Looks like race condition might be happening

Not 100% reproducible, try repeating steps 3 and 4 several times if no repro.

Version tested on:
Version 5.6.0b5 (802d0eaaa43c)
Sun, 15 Jan 2017 18:38:47 GMT
Branch: trunk