Storage manager: Show overall size information and size of Downloads.

chrome/browser/ui/webui/options/chromeos/storage_manager_handler.h

 // Copyright 2016 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_OPTIONS_CHROMEOS_STORAGE_MANAGER_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_OPTIONS_CHROMEOS_STORAGE_MANAGER_HANDLER_H_
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/ui/webui/options/options_ui.h"
 
 namespace chromeos {
 namespace options {
 
 // Storage manager overlay page UI handler.
 class StorageManagerHandler : public ::options::OptionsPageUIHandler {
  public:
   StorageManagerHandler();
   ~StorageManagerHandler() override;
 
   // OptionsPageUIHandler implementation.
   void GetLocalizedValues(base::DictionaryValue* localized_strings) override;
   void InitializePage() override;
 
   // WebUIMessageHandler implementation.
   void RegisterMessages() override;
 
  private:
+  // Handlers of JS messages.
+  void HandleUpdateStorageInfo(const base::ListValue* unused_args);
+  void HandleOpenDownloads(const base::ListValue* unused_args);
+
+  // Requests updating disk space information.
+  void UpdateSizeStat();
+
+  // Callback to update the UI about disk space information.
+  void OnGetSizeStat(int64_t* total_size, int64_t* available_size);
+
+  // Requests updating the size of Downloads directory.
+  void UpdateDownloadsSize();
+
+  // Callback to update the UI about the size of Downloads directory.
+  void OnGetDownloadsSize(int64_t size);
+
+  base::WeakPtrFactory<StorageManagerHandler> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(StorageManagerHandler);
 };
 
 }  // namespace options
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_OPTIONS_CHROMEOS_STORAGE_MANAGER_HANDLER_H_