Remove stl_util's STLDeleteContainerPairSecondPointers.

components/syncable_prefs/pref_model_associator.h

Index: components/syncable_prefs/pref_model_associator.h
diff --git a/components/syncable_prefs/pref_model_associator.h b/components/syncable_prefs/pref_model_associator.h
index 8938d14381eadf8e94f6251e908c1acb0e2f7d1a..34fa739c82d0618edb28074607ec4c478618b10e 100644
--- a/components/syncable_prefs/pref_model_associator.h
+++ b/components/syncable_prefs/pref_model_associator.h
@@ -190,13 +190,12 @@ class PrefModelAssociator
   // Map prefs to lists of observers. Observers will receive notification when
   // a pref changes, including the detail of whether or not the change came
   // from sync.

[battre, 2016/09/22 16:44:24]

I think that I would keep the typedef so that this comment makes sense here.

[Avi (use Gerrit), 2016/09/22 19:17:17]

Fixed.

-  typedef base::ObserverList<SyncedPrefObserver> SyncedPrefObserverList;
-  typedef base::hash_map<std::string, SyncedPrefObserverList*>
-      SyncedPrefObserverMap;
+  using SyncedPrefObserverList = base::ObserverList<SyncedPrefObserver>;
 
   void NotifySyncedPrefObservers(const std::string& path, bool from_sync) const;
 
-  SyncedPrefObserverMap synced_pref_observers_;
+  base::hash_map<std::string, std::unique_ptr<SyncedPrefObserverList>>
+      synced_pref_observers_;
   const PrefModelAssociatorClient* client_;  // Weak.
 
   std::vector<base::Closure> callback_list_;