Replace more ObserverList with base::ObserverList.

net/url_request/url_request_context_getter.h

 // 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.
 
 #ifndef NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_
 #define NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
@@ skipping 50 matching lines @@
   // pending requests can be torn down safely. Right before calling this method,
   // subclasses must ensure GetURLRequestContext returns nullptr, to protect
   // against reentrancy.
   void NotifyContextShuttingDown();
 
  private:
   // OnDestruct is used to ensure deletion on the thread on which the request
   // IO happens.
   void OnDestruct() const;
 
-  ObserverList<URLRequestContextGetterObserver> observer_list_;
+  base::ObserverList<URLRequestContextGetterObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(URLRequestContextGetter);
 };
 
 struct URLRequestContextGetterTraits {
   static void Destruct(const URLRequestContextGetter* context_getter) {
     context_getter->OnDestruct();
   }
 };
 
@@ skipping 16 matching lines @@
 
   URLRequestContext* context_;
   const scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(TrivialURLRequestContextGetter);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_