2nd try: FileAPI: Split recursive remove into multiple tasks.

webkit/fileapi/syncable/syncable_file_system_operation.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/syncable_file_system_operation.h"
 
 #include "base/logging.h"
 #include "webkit/blob/shareable_file_reference.h"
 #include "webkit/fileapi/file_system_context.h"
 #include "webkit/fileapi/file_system_url.h"
@@ skipping 296 matching lines @@
     const StatusCallback& cancel_callback) {
   DCHECK(CalledOnValidThread());
   DCHECK(file_system_operation_);
   completion_callback_ = cancel_callback;
   file_system_operation_->Cancel(
       base::Bind(&self::DidFinish, base::Owned(this)));
 }
 
 LocalFileSystemOperation*
 SyncableFileSystemOperation::AsLocalFileSystemOperation() {
-  NOTREACHED();
-  return NULL;
+  // This must be called for nested sub-task operations
+  // where we don't need extra task queueing.
+  // Just return the internal file_system_operation_ and let this
+  // instance goes away when the operation dies.
+  file_system_operation_->set_termination_callback(
+      base::Bind(&SyncableFileSystemOperation::Destruct,
+                 base::Unretained(this)));
+  return file_system_operation_;
 }
 
 void SyncableFileSystemOperation::CreateSnapshotFile(
     const FileSystemURL& path,
     const SnapshotFileCallback& callback) {
   DCHECK(CalledOnValidThread());
   if (!operation_runner_) {
     callback.Run(base::PLATFORM_FILE_ERROR_NOT_FOUND,
                  base::PlatformFileInfo(), FilePath(), NULL);
     delete file_system_operation_;
@@ skipping 52 matching lines @@
 }
 
 void SyncableFileSystemOperation::AbortOperation(
     const StatusCallback& callback,
     base::PlatformFileError error) {
   callback.Run(error);
   delete file_system_operation_;
   delete this;
 }
 
+void SyncableFileSystemOperation::Destruct() {
+  delete this;
+}
+
 }  // namespace fileapi