Initialize all services as soon as the first service is needed (microsoft#191890)

Fixes microsoft/monaco-editor#4120: initialize all services as soon as the first service is needed

Author: alexdima

src/vs/editor/standalone/browser/standaloneServices.ts

@@ -1114,6 +1114,9 @@ export module StandaloneServices {
 	serviceCollection.set(IInstantiationService, instantiationService);
 
 	export function get<T>(serviceId: ServiceIdentifier<T>): T {
+		if (!initialized) {
+			initialize({});
+		}
 		const r = serviceCollection.get(serviceId);
 		if (!r) {
 			throw new Error('Missing service ' + serviceId);