Eliminate sending NOTIFICATION_TOP_SITES_* from TopSites

chrome/browser/history/chrome_history_client.h

 // Copyright 2014 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_HISTORY_CHROME_HISTORY_CLIENT_H_
 #define CHROME_BROWSER_HISTORY_CHROME_HISTORY_CLIENT_H_
 
 #include "base/macros.h"
 #include "components/history/core/browser/history_client.h"
+#include "components/history/core/browser/top_sites_observer.h"
 
 class BookmarkModel;
+class Profile;
+
+namespace history {
+class TopSites;
+}
 
 // This class implements history::HistoryClient to abstract operations that
 // depend on Chrome environment.
-class ChromeHistoryClient : public history::HistoryClient {
+class ChromeHistoryClient : public history::HistoryClient,
+                            public history::TopSitesObserver {
  public:
-  explicit ChromeHistoryClient(BookmarkModel* bookmark_model);
+  explicit ChromeHistoryClient(BookmarkModel* bookmark_model,
+                               Profile* profile,
+                               history::TopSites* top_sites);
+  virtual ~ChromeHistoryClient();
 
   // history::HistoryClient:
   virtual void BlockUntilBookmarksLoaded() OVERRIDE;
   virtual bool IsBookmarked(const GURL& url) OVERRIDE;
   virtual void GetBookmarks(
       std::vector<history::URLAndTitle>* bookmarks) OVERRIDE;
   virtual void NotifyProfileError(sql::InitStatus init_status) OVERRIDE;
   virtual bool ShouldReportDatabaseError() OVERRIDE;
 
   // KeyedService:
   virtual void Shutdown() OVERRIDE;
 
+  // TopSitesObserver:
+  virtual void TopSitesLoaded(history::TopSites* top_sites) OVERRIDE;
+  virtual void TopSitesChanged(history::TopSites* top_sites) OVERRIDE;
+
  private:
   // The BookmarkModel, this should outlive ChromeHistoryClient.
   BookmarkModel* bookmark_model_;
+  Profile* profile_;
+  history::TopSites* top_sites_;

[brettw, 2014/08/14 22:45:41]

How does the memory management work for this? I guess TopSites is owned by the
profile, but this is some kind of keyed service. What is the lifetime of that in
relation to Profile? It seems like we need to make a less fragile way to handle
this dependency.

[nshaik, 2014/08/15 06:16:12]

Sylvain, can you please answer this question.

 
   DISALLOW_COPY_AND_ASSIGN(ChromeHistoryClient);
 };
 
 #endif  // CHROME_BROWSER_HISTORY_CHROME_HISTORY_CLIENT_H_