Remove uses of base::hash_map from //chrome

chrome/browser/font_family_cache.h

 // Copyright 2014 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_FONT_FAMILY_CACHE_H_
 #define CHROME_BROWSER_FONT_FAMILY_CACHE_H_
 
-#include "base/containers/hash_tables.h"
+#include <unordered_map>
+
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/strings/string16.h"
 #include "base/supports_user_data.h"
 #include "components/prefs/pref_change_registrar.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/common/web_preferences.h"
 
 class PrefService;
 class Profile;
 
 FORWARD_DECLARE_TEST(FontFamilyCacheTest, Caching);
 
 // Caches font family preferences associated with a PrefService. This class
 // relies on the assumption that each concatenation of map_name + '.' + script
 // is a unique string. It also relies on the assumption that the (const char*)
-// keys used in both inner and outer hash_maps are compile time constants.
+// keys used in both inner and outer aps are compile time constants.

[chrisha, 2017/05/23 20:07:59]

maps*

 class FontFamilyCache : public base::SupportsUserData::Data,
                         public content::NotificationObserver {
  public:
   explicit FontFamilyCache(Profile* profile);
   ~FontFamilyCache() override;
 
   // Gets or creates the relevant FontFamilyCache, and then fills |map|.
   static void FillFontFamilyMap(Profile* profile,
                                 const char* map_name,
                                 content::ScriptFontFamilyMap* map);
 
   // Fills |map| with font family preferences.
   void FillFontFamilyMap(const char* map_name,
                          content::ScriptFontFamilyMap* map);
 
  protected:
   // Exposed and virtual for testing.
   // Fetches the font without checking the cache.
   virtual base::string16 FetchFont(const char* script, const char* map_name);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(::FontFamilyCacheTest, Caching);
 
   // Map from script to font.
   // Key comparison uses pointer equality.
-  typedef base::hash_map<const char*, base::string16> ScriptFontMap;
+  using ScriptFontMap = std::unordered_map<const char*, base::string16>;
 
   // Map from font family to ScriptFontMap.
   // Key comparison uses pointer equality.
-  typedef base::hash_map<const char*, ScriptFontMap> FontFamilyMap;
+  using FontFamilyMap = std::unordered_map<const char*, ScriptFontMap>;
 
   // Checks the cache for the font. If not present, fetches the font and stores
   // the result in the cache.
   // This method needs to be very fast, because it's called ~20,000 times on a
   // fresh launch with an empty profile. It's important to avoid unnecessary
   // object construction, hence the heavy use of const char* and the minimal use
   // of std::string.
   // |script| and |map_name| must be compile time constants. Two behaviors rely
   // on this: key comparison uses pointer equality, and keys must outlive the
-  // hash_maps.
+  // maps.
   base::string16 FetchAndCacheFont(const char* script, const char* map_name);
 
   // Called when font family preferences changed.
   // Invalidates the cached entry, and removes the relevant observer.
   // Note: It is safe to remove the observer from the pref change callback.
   void OnPrefsChanged(const std::string& pref_name);
 
   // content::NotificationObserver override.
   // Called when the profile is being destructed.
   void Observe(int type,
@@ skipping 11 matching lines @@
   // Reacts to profile changes.
   PrefChangeRegistrar profile_pref_registrar_;
 
   // Listens for profile destruction.
   content::NotificationRegistrar notification_registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(FontFamilyCache);
 };
 
 #endif  // CHROME_BROWSER_FONT_FAMILY_CACHE_H_