[SyncFS] Make DumpFiles async

chrome/browser/sync_file_system/remote_file_sync_service.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_SYNC_FILE_SYSTEM_REMOTE_FILE_SYNC_SERVICE_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_FILE_SYNC_SERVICE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 102 matching lines @@
   typedef std::map<GURL, std::string> OriginStatusMap;
 
   // For GetRemoteVersions.
   typedef base::Callback<void(SyncStatusCode status,
                               const std::vector<Version>& versions)>
       RemoteVersionsCallback;
   typedef base::Callback<void(SyncStatusCode status,
                               webkit_blob::ScopedFile downloaded)>
       DownloadVersionCallback;
 
+  // For DumpFile.
+  typedef base::Callback<void(scoped_ptr<base::ListValue> list)> ListCallback;
+
   // Creates an initialized RemoteFileSyncService for backend |version|
   // for |context|.
   static scoped_ptr<RemoteFileSyncService> CreateForBrowserContext(
       BackendVersion version,
       content::BrowserContext* context);
 
   // Returns BrowserContextKeyedServiceFactory's an instance of
   // RemoteFileSyncService for backend |version| depends on.
   static void AppendDependsOnFactories(
       BackendVersion version,
@@ skipping 51 matching lines @@
   virtual bool IsConflicting(const fileapi::FileSystemURL& url) = 0;
 
   // Returns the current remote service state (should equal to the value
   // returned by the last OnRemoteServiceStateUpdated notification.
   virtual RemoteServiceState GetCurrentState() const = 0;
 
   // Returns all origins along with an arbitrary string description of their
   // corresponding sync statuses.
   virtual void GetOriginStatusMap(OriginStatusMap* status_map) = 0;
 
-  // Returns file metadata for |origin|.
-  virtual scoped_ptr<base::ListValue> DumpFiles(const GURL& origin) = 0;
+  // Returns file metadata for |origin| to call |callback|.
+  virtual void DumpFiles(const GURL& origin,
+                         const ListCallback& callback) = 0;
 
   // Returns the dump of internal database.
   virtual scoped_ptr<base::ListValue> DumpDatabase() = 0;
 
   // Enables or disables the background sync.
   // Setting this to false should disable the synchronization (and make
   // the service state to REMOTE_SERVICE_DISABLED), while setting this to
   // true does not necessarily mean the service is actually turned on
   // (for example if Chrome is offline the service state will become
   // REMOTE_SERVICE_TEMPORARY_UNAVAILABLE).
@@ skipping 29 matching lines @@
 
   virtual void PromoteDemotedChanges() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RemoteFileSyncService);
 };
 
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_FILE_SYNC_SERVICE_H_