To reproduce:

1. Download and open attached project.
2. Execute menu item: "BUG/Delete scene"

Crash!

...
EditorSceneManager.sceneClosing += SceneClosingCallback;
// Close any scene here
...

static void SceneClosingCallback(Scene scene, bool remove)
{
EditorSceneManager.sceneClosing -= SceneClosingCallback; // Workaround not to make an infinite loop
EditorSceneManager.CloseScene(scene, true);
EditorSceneManager.sceneClosing += SceneClosingCallback;
}

Closing the same scene on EditorSceneManager.sceneClosing callback will result in closing the same scene twice, will try to free memory which is already freed.

Reproduced on: 2017.1.0b1