Add import progress indicator dialog.

chrome/browser/importer/firefox_profile_lock_posix.cc

 // Copyright (c) 2008 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 "chrome/browser/importer/firefox_profile_lock.h"
 
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
@@ skipping 52 matching lines @@
   if (HasAcquired())
     return;
   lock_fd_ = open(lock_file_.value().c_str(), O_CREAT | O_EXCL, 0644);
 }
 
 void FirefoxProfileLock::Unlock() {
   if (!HasAcquired())
     return;
   close(lock_fd_);
   lock_fd_ = -1;
+  file_util::Delete(lock_file_, false);
 }
 
 bool FirefoxProfileLock::HasAcquired() {
   return (lock_fd_ >= 0);
 }