message: Remove unused header from meta_optimizer.cc
diff: @@ -45,7 +45,6 @@ limitations under the License.
  #include "tensorflow/core/lib/core/status.h"
  #include "tensorflow/core/lib/gtl/map_util.h"
  #include "tensorflow/core/util/dump_graph.h"
  -#include "tensorflow/core/util/env_var.h"
  #include "tensorflow/core/util/ptr_util.h"
  namespace tensorflow {
  