Remove uses of base::hash_map from //chrome

chrome/browser/download/chrome_download_manager_delegate.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 #define CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
-#include "base/containers/hash_tables.h"
+#include "base/containers/flat_map.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequenced_task_runner.h"
 #include "chrome/browser/download/download_path_reservation_tracker.h"
 #include "chrome/browser/download/download_target_determiner_delegate.h"
 #include "chrome/browser/download/download_target_info.h"
 #include "chrome/browser/safe_browsing/download_protection_service.h"
 #include "content/public/browser/download_danger_type.h"
 #include "content/public/browser/download_item.h"
@@ skipping 148 matching lines @@
   std::unique_ptr<DownloadPrefs> download_prefs_;
 
   // SequencedTaskRunner to check for file existence. A sequence is used so that
   // a large download history doesn't cause a large number of concurrent disk
   // operations.
   const scoped_refptr<base::SequencedTaskRunner>
       check_for_file_existence_task_runner_;
 
 #if BUILDFLAG(ENABLE_EXTENSIONS)
   // Maps from pending extension installations to DownloadItem IDs.
-  typedef base::hash_map<extensions::CrxInstaller*,
-      content::DownloadOpenDelayedCallback> CrxInstallerMap;
+  typedef base::flat_map<extensions::CrxInstaller*,
+                         content::DownloadOpenDelayedCallback>
+      CrxInstallerMap;
   CrxInstallerMap crx_installers_;
 #endif
 
   content::NotificationRegistrar registrar_;
 
   base::WeakPtrFactory<ChromeDownloadManagerDelegate> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeDownloadManagerDelegate);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_