message: Do not show code lens on namespaces.
  There are too many references for editors to handle well.
diff: @@ -152,6 +152,8 @@ struct TextDocumentCodeLensHandler
  QueryType& type = db->types[symbol.idx];
  if (!type.def)
  continue;
  + if (type.def->kind == ClangSymbolKind::Namespace)
  + continue;
  AddCodeLens("ref", "refs", &common, ref.loc.OffsetStartColumn(0),
  type.uses, type.def->definition_spelling,
  true /*force_display*/);
  