message: Specify lambda return type to work around clang 3.5 build issue
diff: @@ -155,7 +155,7 @@ void RunIndexTests(const std::string& filter_path) {
  // FIXME: promote to utils, find and remove duplicates (ie,
  // cquery_call_tree.cc, maybe something in project.cc).
  - auto basename = [](const std::string& path) {
  + auto basename = [](const std::string& path) -> std::string {
  size_t last_index = path.find_last_of('/');
  if (last_index == std::string::npos)
  return path;
  