Add ProxyResolverFactoryV8Tracing.

net/proxy/network_delegate_error_observer.h

 // 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.
 
 #ifndef NET_PROXY_NETWORK_DELEGATE_ERROR_OBSERVER_H_
 #define NET_PROXY_NETWORK_DELEGATE_ERROR_OBSERVER_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "net/proxy/proxy_resolver_error_observer.h"
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace net {
 
 class NetworkDelegate;
 
 // An implementation of ProxyResolverErrorObserver that forwards PAC script
 // errors to a NetworkDelegate object on the thread it lives on.
 class NET_EXPORT_PRIVATE NetworkDelegateErrorObserver
     : public ProxyResolverErrorObserver {
  public:
   NetworkDelegateErrorObserver(NetworkDelegate* network_delegate,
                                base::MessageLoopProxy* origin_loop);
   ~NetworkDelegateErrorObserver() override;
 
+  static scoped_ptr<ProxyResolverErrorObserver> Create(
+      NetworkDelegate* network_delegate,
+      const scoped_refptr<base::MessageLoopProxy>& origin_loop);
+
   // ProxyResolverErrorObserver implementation.
   void OnPACScriptError(int line_number, const base::string16& error) override;
 
  private:
   class Core;
 
   scoped_refptr<Core> core_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkDelegateErrorObserver);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_NETWORK_DELEGATE_ERROR_OBSERVER_H_