message: core: don't use implicit capture
  Otherwise MSVC is unhappy.
diff: @@ -67,7 +67,7 @@ TEST(ThreadPool, LambdaWithArgs)
  int second = 10;
  const int sum = first + second;
  - tp.enqueue([&second]() {
  + tp.enqueue([first, &second]() {
  second += first;
  });
  