Reproduction steps:

1. Open "MinimalReproProject.zip" project in 5.6.1f1
2. See the Depth of the Sphere and Image
3. Open the same project in 5.6.3p3

Expected Result: The Depth should be the same
Actual Result: The Depth is not written to the shader, thus it doesn't work

Reproduced with: 2017.3.0b1, 2017.2.0f1, 2017.1.1p2, 5.6.3p3, 5.6.2p3, 5.6.2f1, 5.6.1p4, 5.6.1p2
Regression introduced in: 5.6.1p2
Did not reproduce on: 5.6.1p1, 5.6.1f1