statusor::StatusOr

This is a copy of the StatusOr library from tensorflow.

You can find the original source of these files at: https://github.com/tensorflow/tensorflow/blob/master/tensorflow/compiler/xla

If you want to update the libraries, replace the xla namespace with statusor, and fix the includes to replace tensorflow/compiler/xla/ with third_party/statusor. We also use grpc::Status instead of tensorflow's status class. The final change is to remove references to the TF_* macros that cobalt does not use.

This library should be deleted and replaced with Abseil once they add StatusOr.