Refactor sending NOTIFICATION_HISTORY_URL_VISITED

chrome/browser/history/in_memory_history_backend.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.
 
 // The InMemoryHistoryBackend is a wrapper around the in-memory URL database.
 // It maintains an in-memory cache of a subset of history that is required for
 // low-latency operations, such as in-line autocomplete.
 //
 // The in-memory cache provides the following guarantees:
 //  (1.) It will always contain URLRows that either have a |typed_count| > 0; or
 //       that have a corresponding search term, in which case information about
 //       the search term is also stored.
 //  (2.) It will be an actual subset, i.e., it will contain verbatim data, and
 //       will never contain more data that can be found in the main database.
 //
 // The InMemoryHistoryBackend is created on the history thread and passed to the
 // main thread where operations can be completed synchronously. It listens for
 // notifications from the "regular" history backend and keeps itself in sync.
 
 #ifndef CHROME_BROWSER_HISTORY_IN_MEMORY_HISTORY_BACKEND_H_
 #define CHROME_BROWSER_HISTORY_IN_MEMORY_HISTORY_BACKEND_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
+#include "components/history/core/browser/history_service_observer.h"
 #include "components/history/core/browser/keyword_id.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
+class HistoryService;
 class Profile;
 
 namespace base {
 class FilePath;
 }
 
 namespace history {
 
 class InMemoryDatabase;
 struct KeywordSearchUpdatedDetails;
 struct KeywordSearchDeletedDetails;
 class URLDatabase;
 class URLRow;
 struct URLsDeletedDetails;
 struct URLsModifiedDetails;
 
-class InMemoryHistoryBackend : public content::NotificationObserver {
+class InMemoryHistoryBackend : public HistoryServiceObserver,
+                               public content::NotificationObserver {
  public:
   InMemoryHistoryBackend();
   virtual ~InMemoryHistoryBackend();
 
   // Initializes the backend from the history database pointed to by the
   // full path in |history_filename|.
   bool Init(const base::FilePath& history_filename);
 
   // Does initialization work when this object is attached to the history
   // system on the main thread. The argument is the profile with which the
   // attached history service is under.
-  void AttachToHistoryService(Profile* profile);
+  void AttachToHistoryService(Profile* profile,
+                              HistoryService* history_service);
 
   // Deletes all search terms for the specified keyword.
   void DeleteAllSearchTermsForKeyword(KeywordID keyword_id);
 
   // Returns the underlying database associated with this backend. The current
   // autocomplete code was written fro this, but it should probably be removed
   // so that it can deal directly with this object, rather than the DB.
   InMemoryDatabase* db() const {
     return db_.get();
   }
 
+  // HistoryServiceObserver:
+  virtual void OnURLVisited(HistoryService* history_service,
+                            ui::PageTransition transition,
+                            const URLRow& row,
+                            const RedirectList& redirects,
+                            base::Time visit_time) OVERRIDE;
+
   // Notification callback.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) override;
 
  private:
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteAll);
 
   // Handler for HISTORY_URL_VISITED and HISTORY_URLS_MODIFIED.
   void OnURLVisitedOrModified(const URLRow& url_row);
 
   // Handler for HISTORY_URLS_DELETED.
   void OnURLsDeleted(const URLsDeletedDetails& details);
 
   // Handler for HISTORY_KEYWORD_SEARCH_TERM_UPDATED.
   void OnKeywordSearchTermUpdated(const KeywordSearchUpdatedDetails& details);
 
   // Handler for HISTORY_KEYWORD_SEARCH_TERM_DELETED.
   void OnKeywordSearchTermDeleted(const KeywordSearchDeletedDetails& details);
 
   content::NotificationRegistrar registrar_;
 
   scoped_ptr<InMemoryDatabase> db_;
 
   // The profile that this object is attached. May be NULL before
   // initialization.
   Profile* profile_;
+  HistoryService* history_service_;
 
   DISALLOW_COPY_AND_ASSIGN(InMemoryHistoryBackend);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_IN_MEMORY_HISTORY_BACKEND_H_