message: More informative node names in IF lowering.
  (Looks like the original was just a typo.)
diff: @@ -206,7 +206,7 @@ Status CondBuilder::AddOutputs() {
  outputs_.resize(merges.size());
  for (int i = 0; i < then_call_node_->num_outputs(); ++i) {
  TF_RETURN_IF_ERROR(
  - NodeBuilder(graph_->NewName("output"), "Merge", graph_->op_registry(),
  + NodeBuilder(NewName("output"), "Merge", graph_->op_registry(),
  &debug_info_)
  .Input({NodeOut(then_call_node_, i), NodeOut(else_call_node_, i)})
  .Device(if_op_->requested_device())
  @@ -224,7 +224,7 @@ Status CondBuilder::AddOutputs() {
  //
  // We will use this node to rewrite outgoing control edges from lowered 'If'
  // node. All data edges will read tensors directly from Merge nodes.
  - TF_RETURN_IF_ERROR(NodeBuilder(graph_->NewName("branch_executed"), "Merge",
  + TF_RETURN_IF_ERROR(NodeBuilder(NewName("branch_executed"), "Merge",
  graph_->op_registry(), &debug_info_)
  .Input({pivot_t_, pivot_f_})
  .ControlInputs({then_call_node_, else_call_node_})
  