[SystemInfo API] Rewrite storage info provider using storage monitor impl

chrome/browser/storage_monitor/storage_monitor.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_STORAGE_MONITOR_STORAGE_MONITOR_H_
 #define CHROME_BROWSER_STORAGE_MONITOR_STORAGE_MONITOR_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 55 matching lines @@
 
   // Initialize the storage monitor. The provided callback, if non-null,
   // will be called when initialization is complete. If initialization has
   // already completed, this callback will be invoked within the calling stack.
   // Before the callback is run, calls to |GetAttachedStorage| and
   // |GetStorageInfoForPath| may not return the correct results. In addition,
   // registered observers will not be notified on device attachment/detachment.
   // Should be invoked on the UI thread; callbacks will be run on the UI thread.
   void Initialize(base::Closure callback);
 
+  // Register a callback to be called when the initialization is completed. If
+  // the initialization is already completed, the provided callback will be
+  // invoked with the calling stack.
+  void RegisterInitCompletedCallback(base::Closure callback);

[vandebo (ex-Chrome), 2013/05/28 20:00:29]

This is the same as Initialize - remove.

[Hongbo Min, 2013/05/29 01:05:38]

No, from the source code of Initialize, it will invoke Init at last, while
RegisterInitCompletedCallback won't invoke Init. The purpose is to allow the
consumer of StorageMonitor to register callback without invoking Init.

BTW, I don't find Initialize is called in some place, what is it used for?

+
   // Return true if the storage monitor has already been initialized.
   bool IsInitialized();
 
   // Finds the device that contains |path| and populates |device_info|.
   // Should be able to handle any path on the local system, not just removable
   // storage. Returns false if unable to find the device.
   virtual bool GetStorageInfoForPath(
       const base::FilePath& path,
       StorageInfo* device_info) const = 0;
 
 // TODO(gbillock): make this either unnecessary (implementation-specific) or
 // platform-independent.
 #if defined(OS_WIN)
   // Gets the MTP device storage information specified by |storage_device_id|.
   // On success, returns true and fills in |device_location| with device
   // interface details and |storage_object_id| with the string ID that
   // uniquely identifies the object on the device. This ID need not be
   // persistent across sessions.
   virtual bool GetMTPStorageInfoFromDeviceId(
       const std::string& storage_device_id,
       string16* device_location,
       string16* storage_object_id) const = 0;
 #endif
 
 #if defined(OS_LINUX)
   virtual device::MediaTransferProtocolManager*
       media_transfer_protocol_manager() = 0;
 #endif
 
+  // Returns the meta information for all available storages on the system,

[vandebo (ex-Chrome), 2013/05/28 20:00:29]

This change should be done as a separate CL.

[Hongbo Min, 2013/05/29 01:05:38]

OK. I will do that in a separate CL. 

+  // including fixed and removable storage. It may return an empty vector
+  // if the storage metadata retrieval is not completed yet on FILE thread.
+  virtual std::vector<StorageInfo> GetAllAvailableStorages() const;
+
   // Returns information for attached removable storage.
   std::vector<StorageInfo> GetAttachedStorage() const;
 
   void AddObserver(RemovableStorageObserver* obs);
   void RemoveObserver(RemovableStorageObserver* obs);
 
   std::string GetTransientIdForDeviceId(const std::string& device_id);
   std::string GetDeviceIdForTransientId(const std::string& transient_id) const;
 
   virtual void EjectDevice(
@@ skipping 46 matching lines @@
 
   // Map of all the attached removable storage devices.
   RemovableStorageMap storage_map_;
 
   scoped_ptr<TransientDeviceIds> transient_device_ids_;
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_STORAGE_MONITOR_STORAGE_MONITOR_H_