code: private void addRemoteCandidate(TransportCandidate rc) {
          // Add the candidate to the list
          if (rc != null) {
              if (acceptableTransportCandidate(rc, offeredCandidates)) {
                  synchronized (remoteCandidates) {
                      remoteCandidates.add(rc);
                  }
  
                  // Check if the new candidate can be used.
                  checkRemoteCandidate(rc);
              }
          }
      }
docs: Add a remote candidate to the list. The candidate will be checked in
  order to verify if it is usable.
  
  @param rc a remote candidate to add and check.