message: Update document op listener
diff: @@ -3,6 +3,7 @@ import {
  ConnectionState,
  FileMode,
  IChaincode,
  + IChannel,
  IChunkedOp,
  IClientJoin,
  ICodeLoader,
  @@ -208,7 +209,7 @@ export class Document extends EventEmitter {
  public on(event: "connected", listener: (clientId: string) => void): this;
  public on(event: "disconnect", listener: () => void): this;
  public on(event: "error", listener: (error: any) => void): this;
  - public on(event: "op", listener: (message: ISequencedDocumentMessage) => void): this;
  + public on(event: "op", listener: (message: ISequencedDocumentMessage, object: IChannel) => void): this;
  public on(event: "pong" | "processTime", listener: (latency: number) => void): this;
  public on(event: "runtimeChanged", listener: (runtime: IRuntime) => void): this;
  