FBX Crash 4.14.2 with multiple material IDs

@masterwigglestin

Can you provide a test asset? There are two things with this that were brought up when we were investigating. One engineer suggested it was because when the mesh imported it was really small. This was fixed though by putting a check in for these tiny meshes, so that could be likely an issue. and the other which I reported above was to do with material IDs. I was able to see that anything more than 1 material ID would cause the crash.

Thank you!