Translucent material can't get valid custom depth RT on mobile platform and pc preview

1. Drag a sphere static mesh to the scene.
2. Select the sphere StaticMeshActor and check the "Render Custom Pass" option in the detail panel.
3. Create a translucent material and create a SceneTexture node, choose CustomDepth
4. Divide the CustomDepth SceneTexture output  with 2000 and connect the output to the Emissive Color.
5. Change to ES31 preview mode.

The Custom Depth didn't work at translucent material on ES31 preview.

I tried to make a fix and the shevle is 8807814.