Enable TCP preconnect and DNS preresolve on cellular.

chrome/browser/net/prediction_options.h

Index: chrome/browser/net/prediction_options.h
diff --git a/chrome/browser/net/prediction_options.h b/chrome/browser/net/prediction_options.h
index d7114c8778324525305fa31ca0ed8792949e791e..a566645bcdb99bf80a0d1071e1587086a806d7c8 100644
--- a/chrome/browser/net/prediction_options.h
+++ b/chrome/browser/net/prediction_options.h
@@ -30,8 +30,8 @@ enum NetworkPredictionOptions {
 void RegisterPredictionOptionsProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry);
 
-// The following two global functions determine whether predictive network
-// actions are enabled, based on preferences and network type.
+// The following two global functions determine whether prefetching
+// and prerendering are enabled, based on preferences and network type.
 
 // To be executed on the IO thread only.
 bool CanPredictNetworkActionsIO(ProfileIOData* profile_io_data);
@@ -39,6 +39,15 @@ bool CanPredictNetworkActionsIO(ProfileIOData* profile_io_data);
 // To be executed on the UI thread only.
 bool CanPredictNetworkActionsUI(PrefService* prefs);

[mmenke, 2014/08/08 16:05:42]

I think this name is confusing, giving the preconnect is also predicting network
actions.  Suggest calling these CanPrefetch[IO/UI].

Alternatively, could be more specific with CanPrefetchAndPrerender, and rename
the other CanPreresolveAndPreconnect.  A bit wordier, but clearer.  Only
potential issue is we may use them for other decisions, too.  Anyhow, up to you.

[Bence, 2014/08/08 20:10:03]

Done.

 
+// The following two global functions determine whether TCP preconnect
+// and DNS preresolution are enabled, based on preferences.
+
+// To be executed on the IO thread only.
+bool CanPreconnectIO(ProfileIOData* profile_io_data);
+
+// To be executed on the UI thread only.
+bool CanPreconnectUI(PrefService* prefs);
+
 }  // namespace chrome_browser_net
 
 #endif  // CHROME_BROWSER_NET_PREDICTION_OPTIONS_H_