Implement SyncFileSystemService::GetFileSyncStatus method

webkit/fileapi/syncable/local_file_sync_context.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.
 
 #include "webkit/fileapi/syncable/local_file_sync_context.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/platform_file.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 214 matching lines @@
   }
   DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
   LocalFileSystemOperation* operation = CreateFileSystemOperationForSync(
       file_system_context);
   DCHECK(operation);
   operation->GetMetadata(
       url, base::Bind(&LocalFileSyncContext::DidGetFileMetadata,
                       this, callback));
 }
 
+void LocalFileSyncContext::HasPendingLocalChanges(
+    FileSystemContext* file_system_context,
+    const FileSystemURL& url,
+    const HasPendingLocalChangeCallback& callback) {
+  // This gets called on UI thread and relays the task on FILE thread.
+  DCHECK(file_system_context);
+  if (!file_system_context->task_runners()->file_task_runner()->
+          RunsTasksOnCurrentThread()) {
+    DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+    file_system_context->task_runners()->file_task_runner()->PostTask(
+        FROM_HERE,
+        base::Bind(&LocalFileSyncContext::HasPendingLocalChanges,
+                   this, make_scoped_refptr(file_system_context),
+                   url, callback));
+    return;
+  }
+
+  DCHECK(file_system_context->change_tracker());
+  FileChangeList changes;
+  file_system_context->change_tracker()->GetChangesForURL(url, &changes);
+
+  // Fire the callback on UI thread.
+  ui_task_runner_->PostTask(FROM_HERE, base::Bind(callback, !changes.empty()));
+}
+
 void LocalFileSyncContext::AddOriginChangeObserver(
     LocalOriginChangeObserver* observer) {
   origin_change_observers_.AddObserver(observer);
 }
 
 void LocalFileSyncContext::RemoveOriginChangeObserver(
     LocalOriginChangeObserver* observer) {
   origin_change_observers_.RemoveObserver(observer);
 }
 
@@ skipping 313 matching lines @@
                  metadata));
 }
 
 base::TimeDelta LocalFileSyncContext::NotifyChangesDuration() {
   if (mock_notify_changes_duration_in_sec_ >= 0)
     return base::TimeDelta::FromSeconds(mock_notify_changes_duration_in_sec_);
   return base::TimeDelta::FromSeconds(kNotifyChangesDurationInSec);
 }
 
 }  // namespace fileapi