Introduce chrome://flags/#network-prediction-options-for-service-worker

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 651248390f50dbab51520c1f299345963391c2b3..eb46432be7d669f126adfc735d150c020dffb72a 100644
--- a/chrome/browser/net/prediction_options.h
+++ b/chrome/browser/net/prediction_options.h
@@ -32,6 +32,18 @@ enum class NetworkPredictionStatus {
   DISABLED_DUE_TO_NETWORK,
 };
 
+enum class NetworkPredictionOptionsForServiceWorker {
+  PRECONNECT_ONLY,
+  START_SERVICE_WORKER_AND_PRECONNECT,
+  START_SERVICE_WORKER_AND_DEFER_PRECONNECT,
+  START_SERVICE_WORKER_ONLY
+};
+
+extern const char kPreconnectOnly[];
+extern const char kStartServiceWorkerAndPreconnect[];
+extern const char kStartServiceWorkerAndDeferPreconnect[];
+extern const char kStartServiceWorkerOnly[];
+
 void RegisterPredictionOptionsProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry);
 
@@ -54,6 +66,9 @@ bool CanPreresolveAndPreconnectIO(ProfileIOData* profile_io_data);
 // To be executed on the UI thread only.
 bool CanPreresolveAndPreconnectUI(PrefService* prefs);
 
+NetworkPredictionOptionsForServiceWorker
+GetNetworkPredictionOptionsForServiceWorker();
+
 }  // namespace chrome_browser_net
 
 #endif  // CHROME_BROWSER_NET_PREDICTION_OPTIONS_H_