Use Drive v2 API: enable behind --enable-drive-api flag

chrome/browser/chromeos/gdata/gdata_file_system.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_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_
 #pragma once
 
 #include <map>
 #include <set>
@@ skipping 129 matching lines @@
 
     // Triggered when the feed from the server is loaded.
     virtual void OnFeedFromServerLoaded() {}
 
    protected:
     virtual ~Observer() {}
   };
 
   // Initializes the object. This function should be called before any
   // other functions.
-  virtual void Initialize() = 0;
+  virtual void Initialize(bool use_drive_api) = 0;
 
   // Adds and removes the observer.
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
 
   // Starts and stops periodic updates.
   virtual void StartUpdates() = 0;
   virtual void StopUpdates() = 0;
 
   // Checks for updates on the server.
@@ skipping 233 matching lines @@
   GDataFileSystem(
       Profile* profile,
       GDataCache* cache,
       DocumentsServiceInterface* documents_service,
       GDataUploaderInterface* uploader,
       DriveWebAppsRegistryInterface* webapps_registry,
       const base::SequencedWorkerPool::SequenceToken& sequence_token);
   virtual ~GDataFileSystem();
 
   // GDataFileSystem overrides.
-  virtual void Initialize() OVERRIDE;
+  virtual void Initialize(bool use_drive_api) OVERRIDE;
   virtual void AddObserver(Observer* observer) OVERRIDE;
   virtual void RemoveObserver(Observer* observer) OVERRIDE;
   virtual void StartUpdates() OVERRIDE;
   virtual void StopUpdates() OVERRIDE;
   virtual void CheckForUpdates() OVERRIDE;
   virtual void GetFileInfoByResourceId(
       const std::string& resource_id,
       const GetFileInfoWithFilePathCallback& callback) OVERRIDE;
   virtual void Search(const std::string& search_query,
                       const SearchCallback& callback) OVERRIDE;
@@ skipping 849 matching lines @@
   scoped_ptr<PrefChangeRegistrar> pref_registrar_;
 
   // WeakPtrFactory and WeakPtr bound to the UI thread.
   base::WeakPtrFactory<GDataFileSystem> ui_weak_ptr_factory_;
   base::WeakPtr<GDataFileSystem> ui_weak_ptr_;
 
   ObserverList<Observer> observers_;
 
   // The token is used to post tasks to the blocking pool in sequence.
   const base::SequencedWorkerPool::SequenceToken sequence_token_;
+
+  // If true use Drive v2 API instead of Document List API.
+  bool use_drive_api_;
 };
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_