While automode is enabled, ambient color will seemingly at random reset back to it's default gray color

Repro:

1. Open the attached project '2017.1.0b7 test'
2. Open scene 'ambient_bug'
3. With the lighting window open and auto enabled, rotate the cube a couple of times - sometimes also triggers by opening the ambient color picker and hovering cursor over the lighitng window.

3. Observe ambient color resets to gray after a short while

Other things trigger this also, such as switching backend from enlighten to pvr and vice versa

Introduced around 2017.1.0b4-5