Curve with weighted keyframes does not animate properly in the animator.

Repro:
1- Open project in attachment.
2- Open scene 'asdf'.
3- Select game object 'Cube' and open animation window.
4- Move playhead to start animation preview and stop at frame 15 approximatevely.

You'll notice that curve value as shown in the left panel in position attribute does not match visual curve in curve editor.

This is an injection introduced with weighted keyframes.
Reproducible: 2018.1b1, 2018.2a1