[SyncFS] Interface clean up around LocalfileSyncContext::GetFileForLocalSync

chrome/browser/sync_file_system/local/local_file_sync_context.h

 // Copyright 2013 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_LOCAL_LOCAL_FILE_SYNC_CONTEXT_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_SYNC_CONTEXT_H_
 
 #include <deque>
 #include <map>
 #include <set>
@@ skipping 197 matching lines @@
     mock_notify_changes_duration_in_sec_ = duration;
   }
 
  protected:
   // LocalFileSyncStatus::Observer overrides. They are called on IO thread.
   virtual void OnSyncEnabled(const fileapi::FileSystemURL& url) OVERRIDE;
   virtual void OnWriteEnabled(const fileapi::FileSystemURL& url) OVERRIDE;
 
  private:
   typedef base::Callback<void(base::File::Error result)> StatusCallback;
   typedef std::deque<SyncStatusCallback> StatusCallbackQueue;

[peria, 2014/07/14 10:08:37]

How about using std::queue instead of std::deque, if push_front() or pop_back()
are not used?

[tzik, 2014/07/14 10:23:36]

My next CL is going to iterate over this, so it can't be a std::queue.

+  typedef std::deque<fileapi::FileSystemURL> FileSystemURLQueue;

[peria, 2014/07/14 10:08:37]

ditto

   friend class base::RefCountedThreadSafe<LocalFileSyncContext>;
   friend class CannedSyncableFileSystem;
 
   virtual ~LocalFileSyncContext();
 
   void ShutdownOnIOThread();
 
   // Starts a timer to eventually call NotifyAvailableChangesOnIOThread.
   // The caller is expected to update origins_with_pending_changes_ before
   // calling this.
@@ skipping 21 matching lines @@
       const GURL& source_url,
       fileapi::FileSystemContext* file_system_context,
       std::set<GURL>* origins_with_changes,
       SyncStatusCode status);
   void DidInitialize(
       const GURL& source_url,
       fileapi::FileSystemContext* file_system_context,
       SyncStatusCode status);
 
   // Helper routines for GetFileForLocalSync.
-  void GetNextURLsForSyncOnFileThread(
-      fileapi::FileSystemContext* file_system_context,
-      std::deque<fileapi::FileSystemURL>* urls);
+  scoped_ptr<FileSystemURLQueue> GetNextURLsForSyncOnFileThread(
+      fileapi::FileSystemContext* file_system_context);
   void TryPrepareForLocalSync(
       fileapi::FileSystemContext* file_system_context,
-      std::deque<fileapi::FileSystemURL>* urls,
-      const LocalFileSyncInfoCallback& callback);
+      const LocalFileSyncInfoCallback& callback,
+      scoped_ptr<FileSystemURLQueue> urls);
   void DidTryPrepareForLocalSync(
       fileapi::FileSystemContext* file_system_context,
-      std::deque<fileapi::FileSystemURL>* remaining_urls,
+      scoped_ptr<FileSystemURLQueue> remaining_urls,
       const LocalFileSyncInfoCallback& callback,
       SyncStatusCode status,
       const LocalFileSyncInfo& sync_file_info,
       webkit_blob::ScopedFile snapshot);
 
   // Callback routine for PrepareForSync and GetFileForLocalSync.
   void DidGetWritingStatusForSync(
       fileapi::FileSystemContext* file_system_context,
       SyncStatusCode status,
       const fileapi::FileSystemURL& url,
@@ skipping 92 matching lines @@
   ObserverList<LocalOriginChangeObserver> origin_change_observers_;
 
   int mock_notify_changes_duration_in_sec_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileSyncContext);
 };
 
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_SYNC_CONTEXT_H_