Make update over cellular an option for user

chrome/browser/ui/webui/help/version_updater.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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_
 #define CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_
 
 #include <string>
 
 #include "base/callback.h"
 #include "base/strings/string16.h"
 #include "build/build_config.h"
 
 #if defined(OS_CHROMEOS)
 #include "third_party/cros_system_api/dbus/update_engine/dbus-constants.h"
 #endif  // defined(OS_CHROMEOS)
 
 namespace content {
 class WebContents;
 }
 
 // Interface implemented to expose per-platform updating functionality.
 class VersionUpdater {
  public:
   // Update process state machine.
   enum Status {
     CHECKING,
+    NEED_PERMISSION_TO_UPDATE,
     UPDATING,
     NEARLY_UPDATED,
     UPDATED,
     FAILED,
     FAILED_OFFLINE,
     FAILED_CONNECTION_TYPE_DISALLOWED,
     DISABLED,
     DISABLED_BY_ADMIN
   };
 
   // Promotion state (Mac-only).
   enum PromotionState {
     PROMOTE_HIDDEN,
     PROMOTE_ENABLED,
     PROMOTE_DISABLED,
     PROMOTED,
   };
 
   // TODO(jhawkins): Use a delegate interface instead of multiple callback
   // types.
 #if defined(OS_CHROMEOS)
   typedef base::Callback<void(const std::string&)> ChannelCallback;
   typedef base::Callback<void(update_engine::EndOfLifeStatus status)>
       EolStatusCallback;
 #endif
 
   // Used to update the client of status changes. int parameter is the progress
   // and should only be non-zero for the UPDATING state.
+  // std::string parameter is the version of the available update and should be
+  // empty string when update is not available.
+  // int64_t parameter is the size in bytes of the available update and should
+  // be 0 when update is not available.
   // base::string16 parameter is a message explaining a failure.
-  typedef base::Callback<void(Status, int, const base::string16&)>
+  typedef base::Callback<void(Status,
+                              int,
+                              const std::string&,
+                              const int64_t,
+                              const base::string16&)>

[xiyuan, 2017/05/11 20:37:25]

You need to update version_updater_win.cc and version_updater_mac.mm where
StatusCallback is invoked, similar to what you did in version_updater_basic.cc.

[weidongg, 2017/05/11 23:50:44]

Done.

       StatusCallback;
 
   // Used to show or hide the promote UI elements. Mac-only.
   typedef base::Callback<void(PromotionState)> PromoteCallback;
 
   virtual ~VersionUpdater() {}
 
   // Sub-classes must implement this method to create the respective
   // specialization. |web_contents| may be null, in which case any required UX
   // (e.g., UAC to elevate on Windows) may not be associated with any existing
   // browser windows.
   static VersionUpdater* Create(content::WebContents* web_contents);
 
   // Begins the update process by checking for update availability.
   // |status_callback| is called for each status update. |promote_callback|
   // (which is only used on the Mac) can be used to show or hide the promote UI
   // elements.
   virtual void CheckForUpdate(const StatusCallback& status_callback,
                               const PromoteCallback& promote_callback) = 0;
 
+  // Set the update over cellular target in preferences maintained by update
+  // engine. The preferences are latter used by update engine to match the given

[xiyuan, 2017/05/11 20:37:25]

nit: preferences -> |target_version| and |target_size| arguments
latter -> later

"preferences" usually refers to a Pref in PrefService in Chrome so avoid using
that for something else. 

[weidongg, 2017/05/11 23:50:44]

Ok, I see.

+  // target with the server head and to allow update over cellular to this given
+  // target.
+  virtual void SetUpdateOverCellularTarget(const StatusCallback& callback,
+                                           const std::string& target_version,
+                                           int64_t target_size) = 0;
+
 #if defined(OS_MACOSX)
   // Make updates available for all users.
   virtual void PromoteUpdater() const = 0;
 #endif
 
 #if defined(OS_CHROMEOS)
   virtual void SetChannel(const std::string& channel,
                           bool is_powerwash_allowed) = 0;
   virtual void GetChannel(bool get_current_channel,
                           const ChannelCallback& callback) = 0;
   virtual void GetEolStatus(const EolStatusCallback& callback) = 0;
 #endif
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_