Use lossy prefs in the net predictor, and update them more frequently

chrome/browser/net/predictor.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.
 
 // A Predictor object is instantiated once in the browser process, and manages
 // both preresolution of hostnames, as well as TCP/IP preconnection to expected
 // subresources.
 // Most hostname lists are provided by the renderer processes, and include URLs
 // that *might* be used in the near future by the browsing user.  One goal of
 // this class is to cause the underlying DNS structure to lookup a hostname
@@ skipping 220 matching lines @@
 
   // Renderer bundles up list and sends to this browser API via IPC.
   // TODO(csharrison): Use a GURL vector instead to include port and scheme.
   void DnsPrefetchList(const std::vector<std::string>& hostnames);
 
   // May be called from either the IO or UI thread and will PostTask
   // to the IO thread if necessary.
   void DnsPrefetchMotivatedList(const std::vector<GURL>& urls,
                                 UrlInfo::ResolutionMotivation motivation);
 
-  // May be called from either the IO or UI thread and will PostTask
-  // to the IO thread if necessary.
+  // Called from the UI thread in response to the load event.
   void SaveStateForNextStartup();
 
   void SaveDnsPrefetchStateForNextStartup(base::ListValue* startup_list,
-                                          base::ListValue* referral_list,
-                                          base::WaitableEvent* completion);
+                                          base::ListValue* referral_list);
 
   // May be called from either the IO or UI thread and will PostTask
   // to the IO thread if necessary.
   void PreconnectUrl(const GURL& url,
                      const GURL& first_party_for_cookies,
                      UrlInfo::ResolutionMotivation motivation,
                      bool allow_credentials,
                      int count);
 
   void PreconnectUrlOnIOThread(const GURL& url,
@@ skipping 304 matching lines @@
 
  private:
   // These member functions return True for unittests.
   bool CanPrefetchAndPrerender() const override;
   bool CanPreresolveAndPreconnect() const override;
 };
 
 }  // namespace chrome_browser_net
 
 #endif  // CHROME_BROWSER_NET_PREDICTOR_H_