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

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 4f5ce400b56f8d6896e768fcb4e0cb70d944661f..d42d40ad7a7858511fac183115d209d4ab56547a 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -672,6 +672,18 @@ const char kPrerenderFromOmniboxSwitchValueDisabled[] = "disabled";
 //   enabled: Guaranteed prerendering.
 const char kPrerenderFromOmniboxSwitchValueEnabled[] = "enabled";
 
+// Network prediction options for service worker controlled pages.
+// - PreconnectOnly (default): Execute the preconnection on navigations.
+// - StartServiceWorkerAndPreconnect: Start the service worker and execute the
+//   preconnection in parallel on navigations.
+// - StartServiceWorkerAndDeferPreconnect: Start the service worker on
+//   navigations, and defer the preconnection until the service worker startup.
+// - StartServiceWorkerOnly: Start the service worker on navigations and do not
+//   execute the preconnection.
+// See https://crbug.com/727544 for the details.
+const char kNetworkPredictionOptionsForServiceWorker[] =
+    "network-prediction-options-for-service-worker";
+
 // Use IPv6 only for privet HTTP.
 const char kPrivetIPv6Only[]                   = "privet-ipv6-only";