Adds imageWriterPrivate support for Windows

chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc

 // Copyright 2014 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 "base/file_util.h"
 #include "chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.h"
 #include "chrome/browser/extensions/api/image_writer_private/error_messages.h"
+#include "content/public/browser/browser_thread.h"
 
 namespace extensions {
 namespace image_writer {
 
 // Number of bytes for the maximum partition table size.  By wiping this many
 // bytes we can essentially guarantee the header and associated information will
 // be wiped. See http://crbug.com/328246 for more information.
 const int kPartitionTableSize = 1 * 1024;
 
 DestroyPartitionsOperation::DestroyPartitionsOperation(
@@ skipping 19 matching lines @@
 
   scoped_ptr<char[]> buffer(new char[kPartitionTableSize]);
   memset(buffer.get(), 0, kPartitionTableSize);
 
   if (file_util::WriteFile(image_path_, buffer.get(), kPartitionTableSize) !=
       kPartitionTableSize) {
     Error(error::kTempFileError);
     return;
   }
 
-  WriteStart();
+  content::BrowserThread::PostTask(
+      content::BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(&DestroyPartitionsOperation::WriteStart, this));
 }
 
 }  // namespace image_writer
 }  // namespace extensions