Extend the capability of SystemMonitor to support watching storage free space change

chrome/browser/system_monitor/media_device_notifications_chromeos.cc

 // 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.
 
 // chromeos::MediaDeviceNotifications implementation.
 
 #include "chrome/browser/system_monitor/media_device_notifications_chromeos.h"
 
 #include "base/file_path.h"
 #include "base/logging.h"
@@ skipping 24 matching lines @@
   *device_label = UTF8ToUTF16(disk->device_label().empty() ?
                               FilePath(source_path).BaseName().value() :
                               disk->device_label());
   return true;
 }
 
 }  // namespace
 
 using content::BrowserThread;
 
 MediaDeviceNotifications::MediaDeviceNotifications() {

[vandebo (ex-Chrome), 2012/09/11 22:49:27]

In the construction of each implementation you need to set the free space
delegate in SystemMonitor

[Hongbo Min, 2012/09/12 09:24:31]

Done.

   DCHECK(disks::DiskMountManager::GetInstance());
   disks::DiskMountManager::GetInstance()->AddObserver(this);
   CheckExistingMountPointsOnUIThread();
 }
 
 MediaDeviceNotifications::~MediaDeviceNotifications() {
   disks::DiskMountManager* manager = disks::DiskMountManager::GetInstance();
   if (manager) {
     manager->RemoveObserver(this);
   }
@@ skipping 97 matching lines @@
 
   std::string device_id = chrome::MediaStorageUtil::MakeDeviceId(
       chrome::MediaStorageUtil::REMOVABLE_MASS_STORAGE_WITH_DCIM, unique_id);
   mount_map_.insert(std::make_pair(mount_info.mount_path, device_id));
   base::SystemMonitor::Get()->ProcessRemovableStorageAttached(
       device_id,
       device_label,
       mount_info.mount_path);
 }
 
+bool MediaDeviceNotifications::StartWatchingStorage(
+    const FilePath::StringType& path) {
+  return false;
+}
+
+bool MediaDeviceNotifications::StopWatchingStorage(
+    const FilePath::StringType& path) {
+  return false;
+}
+
 }  // namespace chrome