Remove old Authentication code that we don't use or need.

remoting/client/chromoting_client.h

Index: remoting/client/chromoting_client.h
diff --git a/remoting/client/chromoting_client.h b/remoting/client/chromoting_client.h
index 252a2bc1fce74c5d354c2aa8930df32d76b8bded..124e42594c21680c453a7f41450d01d00ddf00b1 100644
--- a/remoting/client/chromoting_client.h
+++ b/remoting/client/chromoting_client.h
@@ -64,10 +64,6 @@ class ChromotingClient : public protocol::ConnectionToHost::HostEventCallback,
       protocol::ConnectionToHost::State state,
       protocol::ConnectionToHost::Error error) OVERRIDE;
 
-  // ClientStub implementation.
-  virtual void BeginSessionResponse(const protocol::LocalLoginStatus* msg,
-                                    const base::Closure& done) OVERRIDE;
-
   // VideoStub implementation.
   virtual void ProcessVideoPacket(const VideoPacket* packet,
                                   const base::Closure& done) OVERRIDE;