net: Fix more clang warnings about missing virtual and OVERRIDE annotations.

net/proxy/proxy_service.cc

 // Copyright (c) 2012 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/proxy/proxy_service.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 355 matching lines @@
   dict->SetString("pac_string", result->ToPacString());
   return dict;
 }
 
 #if defined(OS_CHROMEOS)
 class UnsetProxyConfigService : public ProxyConfigService {
  public:
   UnsetProxyConfigService() {}
   virtual ~UnsetProxyConfigService() {}
 
-  virtual void AddObserver(Observer* observer) {}
-  virtual void RemoveObserver(Observer* observer) {}
-  virtual ConfigAvailability GetLatestProxyConfig(ProxyConfig* config) {
+  virtual void AddObserver(Observer* observer) OVERRIDE {}
+  virtual void RemoveObserver(Observer* observer) OVERRIDE {}
+  virtual ConfigAvailability GetLatestProxyConfig(
+      ProxyConfig* config) OVERRIDE {
     return CONFIG_UNSET;
   }
 };
 #endif
 
 }  // namespace
 
 // ProxyService::InitProxyResolver --------------------------------------------
 
 // This glues together two asynchronous steps:
@@ skipping 1240 matching lines @@
     OnCompletion(result_);
   }
 }
 
 void SyncProxyServiceHelper::OnCompletion(int rv) {
   result_ = rv;
   event_.Signal();
 }
 
 }  // namespace net