To reproduce:
1. Open attached Unity project "UITest"
2. Open "test" scene
3. In the hierarchy, navigate to Canvas --> Image and disable it
4. Go into Play mode
5. Leave The Play mode, go back to Editor
6. Reactivate "Image" GameObject

Expected result: Upon reactivating, the sprite of the GameObject should become visible again
Actual result: The sprite is invisible (See attached gif "UIBug.gif")

Regression first introduced in: 2017.2.0a1
Reproduced on: 2017.2.0a1, 2016.2.0b4
Not reproduced on: 5.5.4p2, 5.6.2p3, 2017.1.0p1