Reproduction steps("GIF" GIF attached):
1. Open or create any Unity project.
2. Create any game object.
3. Attach new "Animation" component for this game object.
4. Go to "Window > Animation" and click "Create".
5. Change game object rotation value while recording animation to any other than 0, 360, 720, etc.
6. Choose any animation time.

Actual result: rotation value resets to starting value.
Expected result: rotation value stays changed.

Additional notes:

• Doesn't reproduce if "Animation" component is not created at first.
• Happens only with rotation value. Scale or position value is possible to change.

Not reproducible with:
5.2.4f1