AU: Try delta updates first, then full updates

src/platform/update_engine/update_check_action.h

 // Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_UPDATE_CHECK_ACTION_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_UPDATE_CHECK_ACTION_H__
 
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 
 #include <string>
 
 #include <curl/curl.h>
 
 #include "base/scoped_ptr.h"
 #include "action.h"
 #include "http_fetcher.h"
 
 // The Update Check action makes an update check request to Omaha and
 // can output the response on the output ActionPipe.
 
-using std::string;
-
 namespace chromeos_update_engine {
 
 // Encodes XML entities in a given string with libxml2. input must be
 // UTF-8 formatted. Output will be UTF-8 formatted.
 std::string XmlEncode(const std::string& input);
 
 // This struct encapsulates the data Omaha gets for the update check.
 // These strings in this struct should not be XML escaped.
 struct UpdateCheckParams {
   UpdateCheckParams()
@@ skipping 98 matching lines @@
 
   // Stores the response from the omaha server
   std::vector<char> response_buffer_;
 
   DISALLOW_COPY_AND_ASSIGN(UpdateCheckAction);
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_UPDATE_CHECK_ACTION_H__