message: Make "isatty" function available on windows in interactive_graphviz.
diff: @@ -48,6 +48,10 @@ limitations under the License.
  #include "util/readline/readline.h"
  #endif
  +#if defined(PLATFORM_WINDOWS)
  +#define isatty _isatty
  +#endif
  +
  namespace xla {
  namespace tools {
  namespace {
  