Reimporting an FBX causes invalid collision on Spline Mesh Components (PhysX)

Reported in UDN: [Link Removed]

Reimporting a static mesh asset from an FBX file causes collision to disappear on spline meshes referencing the static mesh asset.

In investigating this so far, I noticed that USplineMeshComponent::RecreateCollision() gets called twice during the FBX reimport process. And later in FKAggregateGeom::GetAggGeom() and FKConvexElem::DrawElemWire() although the ConvexElem appears to have the correct values, the underlying PhysX collision structure has been reset to default values.

Steps to Reproduce:

1. Enable Show->Collision
2. Add a new Spline Mesh Actor to the scene
3. Import the attached SplineMesh_Original.fbx to the content browser
4. Assign SplineMesh_Original to the static mesh slot on the SplineMesh Actor and note the collision box
5. Right click on SplineMesh_Original and click Reimport with New File, and select SplineMesh_Updated.fbx

 Result

The collision box disappears until you clear the static mesh property and reassign it.

Expected

The collision box is updated to represent the collision for the spline mesh based on the reimported static mesh.