message: Fix invalid reference due to vector resize.
  When creating a new replicate op in the variable runtime reformatting pass, new_replicated_inputs holds references to replicated_inputs, but replicated_inputs could invalidate its elements due to resize.
  Reserve enough space to avoid this problem.
diff: @@ -263,6 +263,7 @@ tf_device::ReplicateOp AddInputsToReplicateOp(
  llvm::SmallVector<std::pair<llvm::ArrayRef<Value>, Type>, 8>
  new_replicated_inputs;
  llvm::SmallVector<llvm::SmallVector<Value, 8>, 8> replicated_inputs;
  + replicated_inputs.reserve(replicate.GetBody().getNumArguments());
  for (auto arg : llvm::enumerate(replicate.GetBody().getArguments())) {
  int64_t i = arg.index();
  replicated_inputs.emplace_back();
  