SDCH: add TimeWeightedMemoryUse

net/sdch/sdch_owner.h

Index: net/sdch/sdch_owner.h
diff --git a/net/sdch/sdch_owner.h b/net/sdch/sdch_owner.h
index 1655275d67a3e8365dc61cf8b01268a5e2884906..bd5b6aa965cafaccf6e8dc1658f76ca36a152e8c 100644
--- a/net/sdch/sdch_owner.h
+++ b/net/sdch/sdch_owner.h
@@ -116,6 +116,10 @@ class NET_EXPORT SdchOwner : public net::SdchObserver,
 
   bool IsPersistingDictionaries() const;
 
+  // Record the lifetime memory use of a specified dictionary, identified by
+  // server hash.
+  void RecordDictionaryLifetime(const std::string& server_hash, size_t size);
+
   // For investigation of http://crbug.com/454198; remove when resolved.
   base::WeakPtr<net::SdchManager> manager_;
   scoped_ptr<net::SdchDictionaryFetcher> fetcher_;
@@ -158,6 +162,10 @@ class NET_EXPORT SdchOwner : public net::SdchObserver,
   // load.
   std::map<std::string, int> use_counts_at_load_;
 
+  // Load times for loaded dictionaries, keyed by server hash. These are used to
+  // track the durations that dictionaries are in memory.
+  std::map<std::string, base::Time> load_times_;
+
   DISALLOW_COPY_AND_ASSIGN(SdchOwner);
 };