[Parser] Don't resolve decl references in the parser if the declaration

has a custom attribute.

Author: hborla

lib/Parse/ParseExpr.cpp

@@ -2255,7 +2255,7 @@ Expr *Parser::parseExprIdentifier() {
   }
 
   Expr *E;
-  if (D == nullptr) {
+  if (D == nullptr || D->getAttrs().hasAttribute<CustomAttr>()) {
     if (name.getBaseName().isEditorPlaceholder()) {
       IDSyntaxContext.setCreateSyntax(SyntaxKind::EditorPlaceholderExpr);
       return parseExprEditorPlaceholder(IdentTok, name.getBaseIdentifier());