message: Remove one level of kExpression nesting
diff: @@ -4679,11 +4679,10 @@ expr_primary_braces
  | range_list_in_braces
  /* Reshape to use kConcatenationExpression instead of kBraceGroup */
  { auto& node = SymbolCastToNode(*$1);
  - $$ = MakeTaggedNode(N::kExpression,
  - MakeTaggedNode(N::kConcatenationExpression,
  + $$ = MakeTaggedNode(N::kConcatenationExpression,
  node[0],
  node[1],
  - node[2])); }
  + node[2]); }
  | streaming_concatenation
  { $$ = MakeTaggedNode(N::kExpression, $1); }
  