message: Add include file which provides the proper std::string mapping.
diff: @@ -21,6 +21,7 @@ limitations under the License.
  #include <vector>
  #include "tensorflow/compiler/xla/statusor.h"
  +#include "tensorflow/compiler/xla/types.h"
  #include "tensorflow/core/lib/core/status.h"
  #include "tensorflow/core/lib/core/stringpiece.h"
  #include "tensorflow/core/lib/gtl/flatset.h"
  