Task Manager Should remember the most recently enabled columns.

chrome/browser/ui/views/new_task_manager_view.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_VIEWS_NEW_TASK_MANAGER_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_NEW_TASK_MANAGER_VIEW_H_
 
 #include <vector>
 
 #include "chrome/browser/ui/host_desktop.h"
@@ skipping 83 matching lines @@
 
   // Initializes the state of the always-on-top setting as the window is shown.
   void InitAlwaysOnTopState();
 
   // Activates the tab associated with the focused row.
   void ActivateFocusedTab();
 
   // Restores saved "always on top" state from a previous session.
   void RetriveSavedAlwaysOnTopState();
 
+  // Restores the saved column visibility from a previous session.
+  void RetrieveSavedColumnVisibility();
+
+  // Updates the visibility of the columns in the table view based on the values
+  // stored in |column_visibility_settings_|.
+  void UpdateColumnVisibility();
+
+  // Stores the current values of columns visibility in
+  // |column_visibility_settings_| to the user prefs.
+  void StoreColumnVisibility();
+
   scoped_ptr<NewTaskManagerView::TableModel> table_model_;
 
   scoped_ptr<views::MenuRunner> menu_runner_;
 
+  // Contains either the retrieved from user preferences columns visibility
+  // settings if any, otherwise it will contain the default column visibility.
+  scoped_ptr<base::DictionaryValue> column_visibility_settings_;

[Lei Zhang, 2015/08/27 01:10:44]

Does this need to be a scoped_ptr? It's always going to a 'non-NULL' scoped_ptr.

[afakhry, 2015/08/27 19:56:52]

It has to be a scoped_ptr<>. DictionaryValue is owned by us and it's non
copiable non assignable. We need to reset it to an new DictionaryValue if
there's one to retrieve from the local state. We can only get it as a pointer or
a scoped_ptr<>.

+
   // We need to own the text of the menu, the Windows API does not copy it.
   base::string16 always_on_top_menu_text_;
 
   views::LabelButton* kill_button_;
   views::Link* about_memory_link_;
   views::TableView* tab_table_;
   views::View* tab_table_parent_;
 
   // all possible columns, not necessarily visible
   std::vector<ui::TableColumn> columns_;
 
   // The host desktop type this task manager belongs to.
   const chrome::HostDesktopType desktop_type_;
 
   // True when the Task Manager window should be shown on top of other windows.
   bool is_always_on_top_;
 
   DISALLOW_COPY_AND_ASSIGN(NewTaskManagerView);
 };
 
 }  // namespace task_management
 
 #endif  // CHROME_BROWSER_UI_VIEWS_NEW_TASK_MANAGER_VIEW_H_