Add commandline flag for service workers.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index aeda0ce0125e58574b5f0aae396799ceab7bf3c9..d3e15c8f61f663358aa8942386d7dbfce303bc6b 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -6812,6 +6812,12 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_FLAGS_ENABLE_STREAMLINED_HOSTED_APPS_DESCRIPTION" desc="Description for the flag to enable streamlined hosted apps.">
         Enables an experimental, more streamlined hosted app experience.
       </message>
+      <message name="IDS_FLAGS_ENABLE_SERVICE_WORKER_NAME" desc="Name of the flag to enable streamlined ServiceWorker.">
+        Enable support for ServiceWorker.
+      </message>
+      <message name="IDS_FLAGS_ENABLE_SERVICE_WORKER_DESCRIPTION" desc="Description for the flag to enable ServiceWorker.">
+        ServiceWorker is a new kind of web worker that can intercept resource requests. See https://github.com/slightlyoff/ServiceWorker for more information.
+      </message>
 
       <!-- Crashes -->
       <message name="IDS_CRASHES_TITLE" desc="Title for the chrome://crashes page.">