Converts a reference into a VFS file path.

def ToPath(self):
    """Converts a reference into a VFS file path."""

    if self.path_type == PathInfo.PathType.OS:
      return os.path.join("fs", "os", *self.path_components)
    elif self.path_type == PathInfo.PathType.TSK:
      return os.path.join("fs", "tsk", *self.path_components)
    elif self.path_type == PathInfo.PathType.REGISTRY:
      return os.path.join("registry", *self.path_components)
    elif self.path_type == PathInfo.PathType.TEMP:
      return os.path.join("temp", *self.path_components)

    raise ValueError("Unsupported path type: %s" % self.path_type)