Repro steps:

1. Open "ReproProject.zip" project
2. Create new scene (Ctrl + N)
3. In the Component bar press on "IsDirtyTester" -> "RUN"

Expected result: The Console should write "Current Scene / State: Untitled / True"
Actual result: The Console outputs "Current Scene / State: / False"

Reproduced with: 2017.2.0b1, 2017.1.0f1, 5.6.2p1, 5.5.4p1, 5.4.5p4

Note:
Scene currentScene = SceneManager.GetActiveScene();
Doesn't set the current scene to the variable if the scene is the one Unity created upon starting a new project/ Creating a New Scene