Implement important sites dialog for desktop.

chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_SETTINGS_SETTINGS_CLEAR_BROWSING_DATA_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_SETTINGS_SETTINGS_CLEAR_BROWSING_DATA_HANDLER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/scoped_observer.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/settings/settings_page_ui_handler.h"
 #include "components/browser_sync/profile_sync_service.h"
 #include "components/browsing_data/core/counters/browsing_data_counter.h"
 
 namespace base {
 class ListValue;
 }
 
 namespace content {
 class WebUI;
+class BrowsingDataFilterBuilder;

[Dan Beam, 2017/05/05 17:52:51]

alpha

[dullweber, 2017/05/09 08:56:39]

I sorted the declarations

 }
 
 namespace settings {
 
 // Chrome browser startup settings handler.
 class ClearBrowsingDataHandler : public SettingsPageUIHandler,
                                  public syncer::SyncServiceObserver {
  public:
   explicit ClearBrowsingDataHandler(content::WebUI* webui);
   ~ClearBrowsingDataHandler() override;
 
   // WebUIMessageHandler implementation.
   void RegisterMessages() override;
   void OnJavascriptAllowed() override;
   void OnJavascriptDisallowed() override;
 
  private:
-  // Observes one |remover| task initiated from ClearBrowsingDataHandler.
-  // Calls |callback| when the task is finished.
-  class TaskObserver;
-
   // Clears browsing data, called by Javascript.
   void HandleClearBrowsingData(const base::ListValue* value);
 
+  // Parses a ListValue with important site information and creates a
+  // BrowsingDataFilterBuilder.
+  std::unique_ptr<content::BrowsingDataFilterBuilder> ProcessImportantSites(
+      const base::ListValue* important_sites);
+
   // Called when a clearing task finished. |webui_callback_id| is provided
   // by the WebUI action that initiated it.
   void OnClearingTaskFinished(const std::string& webui_callback_id);
 
+  // Fetches important sites, called by Javascript.
+  void HandleFetchImportantSites(const base::ListValue* value);
+
   // Initializes the dialog UI. Called by JavaScript when the DOM is ready.
   void HandleInitialize(const base::ListValue* args);
 
   // Implementation of SyncServiceObserver.
   void OnStateChanged(syncer::SyncService* sync) override;
 
   // Updates the footer of the dialog when the sync state changes.
   void UpdateSyncState();
 
   // Finds out whether we should show notice about other forms of history stored
@@ skipping 15 matching lines @@
   // Updates a counter text according to the |result|.
   void UpdateCounterText(
       std::unique_ptr<browsing_data::BrowsingDataCounter::Result> result);
 
   // Cached profile corresponding to the WebUI of this handler.
   Profile* profile_;
 
   // Counters that calculate the data volume for individual data types.
   std::vector<std::unique_ptr<browsing_data::BrowsingDataCounter>> counters_;
 
-  // Observes the currently active data clearing task.
-  std::unique_ptr<TaskObserver> task_observer_;
-
   // ProfileSyncService to observe sync state changes.
   browser_sync::ProfileSyncService* sync_service_;
   ScopedObserver<browser_sync::ProfileSyncService, syncer::SyncServiceObserver>
       sync_service_observer_;
 
   // Whether the sentence about other forms of history stored in user's account
   // should be displayed in the footer. This value is retrieved asynchronously,
   // so we cache it here.
   bool show_history_footer_;
 
   // Whether we should show a dialog informing the user about other forms of
   // history stored in their account after the history deletion is finished.
   bool show_history_deletion_dialog_;
 
   // A weak pointer factory for asynchronous calls referencing this class.

[msramek, 2017/05/05 15:41:55]

Please document when the pointers are invalidated.

The invalidations that we do in HandleInitialize() and OnJavascriptDisallowed()
make sense, since they assure that requests using weak pointers would only live
between opening and closing the dialog. This behavior also works fine for other
users of this |weak_ptr_factory_|, which are the callbacks updating the footer.

But it still might be unexpected for future users.

[dullweber, 2017/05/09 08:56:39]

Done.

   base::WeakPtrFactory<ClearBrowsingDataHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ClearBrowsingDataHandler);
 };
 
 }  // namespace settings
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_SETTINGS_CLEAR_BROWSING_DATA_HANDLER_H_