Add a TODO to remove std.tensor_cast special case in tf-shape-inference.

PiperOrigin-RevId: 308954668
Change-Id: Ib43b5dc3e2053a3a81d911bbad9f432de9b3a28c
diff --git a/tensorflow/compiler/mlir/tensorflow/transforms/shape_inference.cc b/tensorflow/compiler/mlir/tensorflow/transforms/shape_inference.cc
index 466686b..38a1464 100644
--- a/tensorflow/compiler/mlir/tensorflow/transforms/shape_inference.cc
+++ b/tensorflow/compiler/mlir/tensorflow/transforms/shape_inference.cc
@@ -185,6 +185,7 @@
         iter_sink.getOperands().drop_front().take_front(), iter_source,
         tf_dialect);
   }
+  // TODO(b/155227679): Use OpInterface instead of hard-coding for TensorCastOp.
   if (auto tensor_cast = dyn_cast<mlir::TensorCastOp>(op)) {
     return InferShapeForPassThroughOps(
         tensor_cast.getOperation()->getOperands(), op, tf_dialect);