Fix preview when there is a planar reflection

ScriptableRenderPipeline/HDRenderPipeline/CHANGELOG.md

 - Fix the bug preventing decals from coexisting with density volumes
 - Fix issue with alpha tested geometry using planar/triplanar mapping not render correctly or flickering (due to being wrongly alpha tested in depth prepass)
 - Fix meta pass with triplanar (was not handling correctly the normal)
+- Fix preview when a planar reflection is present
+- Fix Camera preview, it is now a Preview cameraType (was a SceneView)
 
 ## [2018.1.0f2]
 

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDRenderPipeline.cs

                     continue;
                 }
 
-                if (camera.cameraType != CameraType.Reflection
+                // Don't render reflection in Preview, it prevent them to display
+                if (camera.cameraType != CameraType.Reflection && camera.cameraType != CameraType.Preview
                     // Planar probes rendering is not currently supported for orthographic camera
                     // Avoid rendering to prevent error log spamming
                     && !camera.orthographic)