message: gltfio: fix bad color in ubershader mode.
diff: @@ -495,17 +495,19 @@ bool FAssetLoader::createPrimitive(const cgltf_primitive* inPrim, Primitive* out
  if (mMaterials->getSource() == LOAD_UBERSHADERS) {
  if (!hasUv0) {
  needsDummyData = true;
  - vbb.attribute(VertexAttribute::UV0, slot++, VertexBuffer::AttributeType::USHORT2);
  + vbb.attribute(VertexAttribute::UV0, slot, VertexBuffer::AttributeType::USHORT2);
  }
  if (!hasUv1) {
  needsDummyData = true;
  - vbb.attribute(VertexAttribute::UV1, slot++, VertexBuffer::AttributeType::USHORT2);
  + vbb.attribute(VertexAttribute::UV1, slot, VertexBuffer::AttributeType::USHORT2);
  }
  if (!hasVertexColor) {
  needsDummyData = true;
  - vbb.attribute(VertexAttribute::COLOR, slot++, VertexBuffer::AttributeType::UBYTE4);
  + vbb.attribute(VertexAttribute::COLOR, slot, VertexBuffer::AttributeType::UBYTE4);
  vbb.normalized(VertexAttribute::COLOR);
  }
  + if (needsDummyData) {
  + slot++;
  }
  int bufferCount = slot;
  