Repro:

1. Open the attached project, add ' Debug.Log(_image.fillAmount); ' just after fillAmount is set to 'GaugeControl.cs'.

2. Run, observe that the sprite is longer visible after it's fillAmount is set to 0.0f once in the coroutine despite that the value is actually changed.

3. Can only be reproduced in a coroutine, changing value to 0.0f and to other value in the same frame works fine.

Placing this snippet in a 'INumerator Start()', is enough to reproduce this:

yield return 0;
_image.fillAmount = 0.000f;
yield return 0;
_image.fillAmount = 0.25f;
yield return 0;

Regression in 4.6 b16