message: reuse RefCountIsOne function member
diff: @@ -87,7 +87,7 @@ inline bool RefCounted::Unref() const {
  DCHECK_GT(ref_.load(), 0);
  // If ref_==1, this object is owned only by the caller. Bypass a locked op
  // in that case.
  - if (ref_.load(std::memory_order_acquire) == 1 || ref_.fetch_sub(1) == 1) {
  + if (RefCountIsOne() || ref_.fetch_sub(1) == 1) {
  // Make DCHECK in ~RefCounted happy
  DCHECK((ref_.store(0), true));
  delete this;
  