AU: Use Omaha ID rather than MAC address in delta updater

src/platform/update_engine/install_action_unittest.cc

 // Copyright (c) 2009 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 <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <utime.h>
 #include <set>
 #include <string>
 #include <vector>
 #include "base/string_util.h"
 #include <gtest/gtest.h>
 #include "update_engine/delta_diff_generator.h"
 #include "update_engine/filesystem_iterator.h"
 #include "update_engine/install_action.h"
 #include "update_engine/test_utils.h"
 #include "update_engine/utils.h"
 
 using chromeos_update_engine::DeltaDiffGenerator;
 using chromeos_update_engine::kRandomString;
 using chromeos_update_engine::System;
-using chromeos_update_engine::WriteFile;
+using chromeos_update_engine::utils::WriteFile;
 using std::set;
 using std::string;
 using std::vector;
 
 namespace {
 void GenerateFilesAtPath(const string& base) {
   EXPECT_EQ(0, System(StringPrintf("echo hi > %s/hi", base.c_str())));
   EXPECT_EQ(0, System(StringPrintf("ln %s/hi %s/hard_link", base.c_str(),
                                    base.c_str())));
   EXPECT_EQ(0, System(StringPrintf("mkdir -p %s/dir", base.c_str())));
@@ skipping 230 matching lines @@
 
   InstallPlan install_plan(false, "", "", "no_such_file", "install_path");
   feeder_action.set_obj(install_plan);
 
   processor.StartProcessing();
   EXPECT_FALSE(processor.IsRunning()) << "Update to handle async actions";
   EXPECT_TRUE(collector_action.object().empty());
 }
 
 }  // namespace chromeos_update_engine