To reproduce:

1. Download and open attached "Case 127141 - MaterialPropBlock_vs_MetaShaderPass.zip" project.
2. Open "test" scene.
3. Change Editor scene shading mode to be "Lit Clustering".
4. Generate Lighting in the scene.
5. Enter Game mode.
6. Get back to the scene view.
7. Select "Plane" game object and alter the SetMaterialPropBlock component tint color of that object.
8. Notice that changing the tint color changes "Plane" object's mesh color.
9. Select "-> Terrain <-" game object and alter the SetMaterialPropBlock component tint color of that object.

Expected result: Selected color reflects on a terrain mesh in the scene view just like "Plane" mesh.
Actual result: Meta pass is not updated. Terrain's mesh does not change its color according to the Albedo Tint pallete.

Reproduced with: 2017.3.0a2, 2017.2.0b5, 2017.1.0p2, 5.6.3f1.

Notes: Couldn't test on earlier versions because of script errors. Everything works correctly on Plane mesh, so it can be used as a reference to correct behavior.
- Issue has been introduced because of API change. It used to work before DynamicGI.UpdateMaterials() API was deprecated.

Verified with: 2017.3.0b9, 2017.1.2p4