Dynamic Directional Shadows do not work with Planar Reflections

Movable/Stationary dynamic shadow distance in the Directional light is not captured in the Planar Reflection.

Note that Point and Spot Lights box cast shadows that can be rendered in the reflection.

1. Open UE4
2. Enable Planar Reflections in the Project Settings
3. Restart the Editor
4. Add a Planar Reflection Actor to the default scene
5. Change the DIrectional light to Movable
6. Setup an actor to cast shadows that can be seen in the reflection

Regression: No

Results: Directional dynamic shadows do not show in the reflection
Expected: Directional dynamic shadows will be rendered in the reflection