message: Remove unused header file
diff: @@ -17,7 +17,6 @@ limitations under the License.
  #define TENSORFLOW_COMPILER_MLIR_LITE_TRANSFORMS_PASSES_H_
  #include "llvm/ADT/ArrayRef.h"
  -#include "llvm/ADT/StringRef.h"
  namespace mlir {
  class FunctionPassBase;
  