message: Prevent undefined shift in TimestampWrapAroundHandler::Unwrap
  If num_wrap_ is zero this will result in a left shift of a
  negative number, which is undefined behaviour.
  Cr-Commit-Position: refs/heads/master@{#31608}
diff: @@ -247,7 +247,7 @@ int64_t TimestampWrapAroundHandler::Unwrap(uint32_t ts) {
  ++num_wrap_;
  } else if ((ts - last_ts_) > 0xf0000000) {
  // Backwards wrap. Unwrap with last wrap count and don't update last_ts_.
  - return ts + ((num_wrap_ - 1) << 32);
  + return ts + (num_wrap_ - 1) * (int64_t{1} << 32);
  }
  last_ts_ = ts;
  