Stop setting invalid value to the |tab_id| field of fileBrowserHandler API.

chrome/browser/chromeos/extensions/file_manager/private_api_tasks.cc

 // 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.
 
 #include "chrome/browser/chromeos/extensions/file_manager/private_api_tasks.h"
 
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/extensions/file_manager/private_api_util.h"
 #include "chrome/browser/chromeos/file_manager/file_tasks.h"
 #include "chrome/browser/chromeos/file_manager/fileapi_util.h"
@@ skipping 71 matching lines @@
   for (size_t i = 0; i < params->file_urls.size(); i++) {
     const FileSystemURL url =
         file_system_context->CrackURL(GURL(params->file_urls[i]));
     if (!chromeos::FileSystemBackend::CanHandleURL(url)) {
       error_ = kInvalidFileUrl;
       return false;
     }
     file_urls.push_back(url);
   }
 
-  const int32 tab_id = file_manager::util::GetTabId(dispatcher());
   return file_manager::file_tasks::ExecuteFileTask(
       GetProfile(),
       source_url(),
       extension_->id(),
-      tab_id,
       task,
       file_urls,
       base::Bind(&FileBrowserPrivateExecuteTaskFunction::OnTaskExecuted, this));
 }
 
 void FileBrowserPrivateExecuteTaskFunction::OnTaskExecuted(bool success) {
   SetResult(new base::FundamentalValue(success));
   SendResponse(true);
 }
 
@@ skipping 97 matching lines @@
     SetResult(new base::FundamentalValue(true));
     return true;
   }
 
   file_manager::file_tasks::UpdateDefaultTask(
       GetProfile()->GetPrefs(), params->task_id, suffixes, mime_types);
   return true;
 }
 
 }  // namespace extensions