message: fix CubemapUtils::processSingleThreaded()
  the state wasn't initialized from the user given prototype
diff: @@ -97,6 +97,8 @@ void CubemapUtils::processSingleThreaded(
  const size_t dim = cm.getDimensions();
  STATE s;
  + s = prototype;
  +
  for (size_t faceIndex = 0; faceIndex < 6; faceIndex++) {
  const Cubemap::Face f = (Cubemap::Face)faceIndex;
  Image& image(cm.getImageForFace(f));
  