Remove some linked_ptr c/b/extension

chrome/browser/extensions/api/mdns/dns_sd_registry.h

 // Copyright 2013 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 CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_
 #define CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_
 
 #include <map>
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/macros.h"
-#include "base/memory/linked_ptr.h"
 #include "base/observer_list.h"
 #include "chrome/browser/extensions/api/mdns/dns_sd_delegate.h"
 
 namespace local_discovery {
 class ServiceDiscoverySharedClient;
 class ServiceDiscoveryClient;
 }
 
 namespace extensions {
 
@@ skipping 61 matching lines @@
 
     const DnsSdRegistry::DnsSdServiceList& GetServiceList();
 
    private:
     int ref_count;
     std::unique_ptr<DnsSdDeviceLister> lister_;
     DnsSdRegistry::DnsSdServiceList service_list_;
     DISALLOW_COPY_AND_ASSIGN(ServiceTypeData);
   };
 
-  // Maps service types to associated data such as listers and service lists.
-  typedef std::map<std::string, linked_ptr<ServiceTypeData> >
-      DnsSdServiceTypeDataMap;
-
   virtual DnsSdDeviceLister* CreateDnsSdDeviceLister(
       DnsSdDelegate* delegate,
       const std::string& service_type,
       local_discovery::ServiceDiscoverySharedClient* discovery_client);
 
   // DnsSdDelegate implementation:
   void ServiceChanged(const std::string& service_type,
                       bool added,
                       const DnsSdService& service) override;
   void ServiceRemoved(const std::string& service_type,
                       const std::string& service_name) override;
   void ServicesFlushed(const std::string& service_type) override;
 
-  DnsSdServiceTypeDataMap service_data_map_;
+  std::map<std::string, std::unique_ptr<ServiceTypeData>> service_data_map_;
 
  private:
   void DispatchApiEvent(const std::string& service_type);
   bool IsRegistered(const std::string& service_type);
 
   scoped_refptr<local_discovery::ServiceDiscoverySharedClient>
       service_discovery_client_;
   base::ObserverList<DnsSdObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(DnsSdRegistry);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_