When importing an Animation from a Project earlier than 2018.2.7f1, the Sorting Orders of animated SkinnedMeshRenderers are supposed to be Animated, this seems to work in the Editor in the Animation Window fine, but when instantiating the Animator prefab in Play Mode, it does not Animate correctly and seems to retain Default values throughout the Animation, even though they should be Animated. In a Simple Example, it works, in a more Complex Character Example it does not

To reproduce:

1. Download attached project from the link and open in Unity
2. Open "SampleScene" scene
3. Enter to Play mode
4. Press Space button
5. Notice the Sorting Orders of the Pants on the thighs of the Character is not Animated in the Kick_Right Animation state as they should be

Notes:
- This issue reproduces on both Windows and macOS
- Starting from Unity 2018.2.14f1 everything starts to work as Expected in the Build, but not in the Editor
- Could not properly check Regression version because Project freezes almost all the time or just becomes Corrupted
- Project link and More information is in the Comments section

Reproduced on Unity 2018.2.21f1, 2018.3.7f1, 2019.1.0b5 and 2019.2.0a7
Not reproduced on Unity 2018.1.9f2
Regression is somewhere in Unity 2018.2