message: Optimize format flag check when it is empty
diff: @@ -267,7 +267,7 @@ SyntaxHighlighterPtr SyntaxHighlighter::ForItem(const CatalogItem& item, int kin
  all->Add(placeholders);
  }
  - if (kindsMask & Placeholder)
  + if (!fmt.empty() && (kindsMask & Placeholder))
  {
  if (fmt == "php")
  {
  