Remove warning about std::map::emplace

base/containers/mru_cache.h

Index: base/containers/mru_cache.h
diff --git a/base/containers/mru_cache.h b/base/containers/mru_cache.h
index 7c684a9690da9b40280f20598edaa88fd71aa6b7..d20ef132b529ecce1032005476f936e05cf708c0 100644
--- a/base/containers/mru_cache.h
+++ b/base/containers/mru_cache.h
@@ -97,8 +97,8 @@ class MRUCacheBase {
       ShrinkToSize(max_size_ - 1);
     }
 
-    ordering_.push_front(value_type(key, std::forward<Payload>(payload)));
-    index_.insert(std::make_pair(key, ordering_.begin()));
+    ordering_.emplace_front(key, std::forward<Payload>(payload));
+    index_.emplace(key, ordering_.begin());

[jdoerrie, 2017/04/25 11:33:47]

While |index_|'s type is a template parameter, it defaults to std::map. The
corresponding unit tests cover this case, thus this should be sufficient to
check the feature's availability.

     return ordering_.begin();
   }