message: Housekeeping: Declare DataChannelController immovable
  This should be done according to the C++ style guide.
  Cr-Commit-Position: refs/heads/master@{#30204}
diff: @@ -29,6 +29,12 @@ class DataChannelController : public DataChannelProviderInterface,
  public:
  explicit DataChannelController(PeerConnection* pc) : pc_(pc) {}
  + // Not copyable or movable.
  + DataChannelController(DataChannelController&) = delete;
  + DataChannelController& operator=(const DataChannelController& other) = delete;
  + DataChannelController(DataChannelController&&) = delete;
  + DataChannelController& operator=(DataChannelController&& other) = delete;
  +
  // Implements DataChannelProviderInterface.
  bool SendData(const cricket::SendDataParams& params,
  const rtc::CopyOnWriteBuffer& payload,
  