message: Add more informative logging if `TF_RET_CHECK(arg_shape.handle_type != DT_INVALID)` fails.
diff: @@ -1568,7 +1568,8 @@ Status DistributedTPURewritePass::GetArgAndRetvalShapes(
  arg_shape.shape = TensorShape(); // Variables are always scalars.
  arg_shape.handle_shape = info->handle_shape;
  arg_shape.handle_type = info->handle_type;
  - TF_RET_CHECK(arg_shape.handle_type != DT_INVALID);
  + TF_RET_CHECK(arg_shape.handle_type != DT_INVALID)
  + << " input edge: " << input_edges[edge_pos]->DebugString();
  ++edge_pos;
  }
  