1) Open the attached project
2) Open the "TestScene" scene.
3) Go in play mode.

Result: "Assembly Cache Should Be Empty" message appears in the console.
Expected: No message in the console.

Repro with Unity 2019.3.13f1 (the bug is likely there since the beginning of director, in 2017).

This project contains a Monobehaviour on the Gameobject that contains the PlayableDirector. This monobehaviour evaluates a Director during OnEnable:

```
[ExecuteInEditMode]
public class EvaluateTimeline : MonoBehaviour
{
void OnEnable()
{
var director = GetComponent<PlayableDirector>();
director.Evaluate();
}
}
```