The issue arises when Aspect Ratio Fitter is used on an object inside a Grid Layout Group item that is located inside dynamically sized window(window using Content Size Fitter).

This issue is a combination of Grid Layout Group, Content Size Fitter and Aspect Ratio Fitter component interaction.

How to reproduce:
1. Open Unity
2. Load QA tester submitted project
3. Open 'UI.unity' scene
3. Notice three buttons inside the window
4. Select 'Button 1'
5. Enable Aspect Ratio Fitter

Expected result: Aspect Ratio Fitter only interacts with the button it is attached to.
Actual result: Aspect Ratio Fitter moves other buttons out of their positions.

Regression first introduced in - 2017.3.0a1
Reproducible with - 2017.3.0a1, 2017.3.0b3, 2017.3.0b4
Not reproducible with - 2017.1.0p2, 2017.1.1p4, 2017.2.0b1, 2017.2.0f2, 2018.1.0a1