Remove unused HostResolver::Observer.

net/socket/socks_client_socket_unittest.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/socket/socks_client_socket.h"
 
 #include "net/base/address_list.h"
 #include "net/base/net_log.h"
 #include "net/base/net_log_unittest.h"
 #include "net/base/mock_host_resolver.h"
@@ skipping 93 matching lines @@
     NOTIMPLEMENTED();
     return ERR_UNEXPECTED;
   }
 
   virtual void CancelRequest(RequestHandle req) OVERRIDE {
     EXPECT_TRUE(HasOutstandingRequest());
     EXPECT_EQ(outstanding_request_, req);
     outstanding_request_ = NULL;
   }
 
-  virtual void AddObserver(Observer* observer) OVERRIDE {}
-  virtual void RemoveObserver(Observer* observer) OVERRIDE {}
-
   bool HasOutstandingRequest() {
     return outstanding_request_ != NULL;
   }
 
  private:
   RequestHandle outstanding_request_;
 
   DISALLOW_COPY_AND_ASSIGN(HangingHostResolverWithCancel);
 };
 
@@ skipping 270 matching lines @@
   // Disconnect the SOCKS socket -- this should cancel the outstanding resolve.
   user_sock_->Disconnect();
 
   EXPECT_FALSE(hanging_resolver->HasOutstandingRequest());
 
   EXPECT_FALSE(user_sock_->IsConnected());
   EXPECT_FALSE(user_sock_->IsConnectedAndIdle());
 }
 
 }  // namespace net