Unreserve braced enum variants in value namespace

compiler/rustc_ast/src/ast.rs

@@ -2664,7 +2664,7 @@ impl VariantData {
     }
 
     /// Return the `NodeId` of this variant's constructor, if it has one.
-    pub fn ctor_id(&self) -> Option<NodeId> {
+    pub fn ctor_node_id(&self) -> Option<NodeId> {
         match *self {
             VariantData::Struct(..) => None,
             VariantData::Tuple(_, id) | VariantData::Unit(id) => Some(id),