Use update instead of manually tring to re-register

src/vs/workbench/contrib/webview/browser/pre/host.js

@@ -55,8 +55,7 @@
 					return resolveWorkerReady();
 				} else {
 					// If we have the wrong version, try once to unregister and re-register
-					return registration.unregister()
-						.then(() => navigator.serviceWorker.register('service-worker.js'))
+					return registration.update()
 						.then(() => navigator.serviceWorker.ready)
 						.finally(resolveWorkerReady);
 				}