Replace uses of hash_map in //base

chromeos/system/statistics_provider.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 "chromeos/system/statistics_provider.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/command_line.h"
+#include "base/containers/flat_map.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/json/json_file_value_serializer.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/singleton.h"
 #include "base/path_service.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ skipping 234 matching lines @@
 
   bool load_statistics_started_;
   NameValuePairsParser::NameValueMap machine_info_;
   MachineFlags machine_flags_;
   base::CancellationFlag cancellation_flag_;
   // |on_statistics_loaded_| protects |machine_info_| and |machine_flags_|.
   base::WaitableEvent on_statistics_loaded_;
   bool oem_manifest_loaded_;
   std::string region_;
   std::unique_ptr<base::Value> regional_data_;
-  base::hash_map<std::string, RegionDataExtractor> regional_data_extractors_;
+  base::flat_map<std::string, RegionDataExtractor> regional_data_extractors_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(StatisticsProviderImpl);
 };
 
 bool StatisticsProviderImpl::WaitForStatisticsLoaded() {
   CHECK(load_statistics_started_);
   if (on_statistics_loaded_.IsSignaled())
     return true;
 
@@ skipping 349 matching lines @@
   return StatisticsProviderImpl::GetInstance();
 }
 
 // static
 void StatisticsProvider::SetTestProvider(StatisticsProvider* test_provider) {
   g_test_statistics_provider = test_provider;
 }
 
 }  // namespace system
 }  // namespace chromeos