ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced

ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced (e.g. RegisterIndex of the texture is [3] or [7]) because FMeshRenderer::RenderMaterialTexCoordScales() uses a black clear value with an alpha value of 1.0

See the linked UDN for additional details.

1. Create a Material that uses a WorldPositionOffset of 0,0,100
2. Assign the Material to a mesh in the scene
3.  Set the viewport view mode to Optimization Viewmodes>Material Texture Scales.

Expected
ExportMaterialUVDensities() gets the correct values where the alpha channel is referenced (e.g. RegisterIndex of the texture is [3] or [7]).

Actual

ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced (e.g. RegisterIndex of the texture is [3] or [7]).