Use base::flat_set<> rather than std::set<> for ResourceType set

components/safe_browsing_db/remote_database_manager.h

 // Copyright 2015 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.
 //
 // Implementation of the SafeBrowsingDatabaseManager that sends URLs
 // via IPC to a database that chromium doesn't manage locally.
 
 #ifndef COMPONENTS_SAFE_BROWSING_DB_REMOTE_DATABASE_MANAGER_H_
 #define COMPONENTS_SAFE_BROWSING_DB_REMOTE_DATABASE_MANAGER_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
+#include "base/containers/flat_set.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "components/safe_browsing_db/database_manager.h"
 #include "url/gurl.h"
 
 namespace net {
 class URLRequestContextGetter;
 }
 
@@ skipping 42 matching lines @@
   // RemoteSafeBrowsingDatabaseManager implementation
   //
 
  private:
   ~RemoteSafeBrowsingDatabaseManager() override;
   class ClientRequest;  // Per-request tracker.
 
   // Requests currently outstanding.  This owns the ptrs.
   std::vector<ClientRequest*> current_requests_;
 
-  std::set<content::ResourceType> resource_types_to_check_;
+  base::flat_set<content::ResourceType> resource_types_to_check_;
 
   friend class base::RefCountedThreadSafe<RemoteSafeBrowsingDatabaseManager>;
   DISALLOW_COPY_AND_ASSIGN(RemoteSafeBrowsingDatabaseManager);
 };  // class RemoteSafeBrowsingDatabaseManager
 
 }  // namespace safe_browsing
 
 #endif  // COMPONENTS_SAFE_BROWSING_DB_REMOTE_DATABASE_MANAGER_H_