Don't consider sources as Initializer or Listener

Update SpringApplication so that source objects are no longer considered
as ApplicationListeners or ApplicationContextInitializer.

spring-boot/src/main/java/org/springframework/boot/SpringApplication.java

@@ -304,9 +304,6 @@ public class SpringApplication {
 
 		ApplicationEventMulticaster multicaster = createApplicationEventMulticaster();
 		try {
-			Set<Object> sources = getSources();
-			registerListenerAndInitializerSources(multicaster, sources);
-
 			// Allow logging and stuff to initialize very early
 			multicaster.multicastEvent(new ApplicationStartedEvent(this, args));
 
@@ -319,17 +316,14 @@ public class SpringApplication {
 			multicaster.multicastEvent(new ApplicationEnvironmentPreparedEvent(this,
 					args, environment));
 
-			// Sources might have changed when environment was applied
-			sources = getSources();
+			// Load the sources (might have changed when environment was applied)
+			Set<Object> sources = getSources();
 			Assert.notEmpty(sources, "Sources must not be empty");
 
 			if (this.showBanner) {
 				printBanner();
 			}
 
-			// Some sources might be listeners
-			registerListenerAndInitializerSources(multicaster, sources);
-
 			// Create, load, refresh and run the ApplicationContext
 			context = createApplicationContext();
 			registerApplicationEventMulticaster(context, multicaster);
@@ -391,18 +385,6 @@ public class SpringApplication {
 		}
 	}
 
-	private void registerListenerAndInitializerSources(
-			ApplicationEventMulticaster multicaster, Set<Object> sources) {
-		for (Object object : sources) {
-			if (object instanceof ApplicationListener) {
-				multicaster.addApplicationListener((ApplicationListener<?>) object);
-			}
-			if (object instanceof ApplicationContextInitializer) {
-				addInitializers((ApplicationContextInitializer<?>) object);
-			}
-		}
-	}
-
 	private void registerApplicationEventMulticaster(
 			ConfigurableApplicationContext context,
 			ApplicationEventMulticaster multicaster) {