Adding performance tests for HQP that represent importance of optimising HistoryItemsForTerms method

components/history/core/browser/history_service.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 COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 534 matching lines @@
  private:
   class BackendDelegate;
   friend class base::RefCountedThreadSafe<HistoryService>;
   friend class BackendDelegate;
   friend class favicon::FaviconService;
   friend class HistoryBackend;
   friend class HistoryQueryTest;
   friend class ::HistoryQuickProviderTest;
   friend class HistoryServiceTest;
   friend class ::HistoryURLProvider;
+  friend class HQPPerfTestOnePopularURL;
   friend class ::InMemoryURLIndexTest;
   friend class ::SyncBookmarkDataTypeControllerTest;
   friend class ::TestingProfile;
   friend std::unique_ptr<HistoryService> CreateHistoryService(
       const base::FilePath& history_dir,
       bool create_db);
 
   // Called on shutdown, this will tell the history backend to complete and
   // will release pointers to it. No other functions should be called once
   // cleanup has happened that may dispatch to the history thread (because it
@@ skipping 266 matching lines @@
 
   // All vended weak pointers are invalidated in Cleanup().
   base::WeakPtrFactory<HistoryService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HistoryService);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_