AbstractBeanFactory consistently guards add/remove operations against alreadyCreated Set

Issue: SPR-14269

spring-beans/src/main/java/org/springframework/beans/factory/support/AbstractBeanFactory.java

@@ -1504,10 +1504,11 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 	protected void markBeanAsCreated(String beanName) {
 		if (!this.alreadyCreated.contains(beanName)) {
 			synchronized (this.mergedBeanDefinitions) {
-				if (this.alreadyCreated.add(beanName)) {
+				if (!this.alreadyCreated.contains(beanName)) {
 					// Let the bean definition get re-merged now that we're actually creating
 					// the bean... just in case some of its metadata changed in the meantime.
 					clearMergedBeanDefinition(beanName);
+					this.alreadyCreated.add(beanName);
 				}
 			}
 		}
@@ -1518,7 +1519,9 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 	 * @param beanName the name of the bean
 	 */
 	protected void cleanupAfterBeanCreationFailure(String beanName) {
-		this.alreadyCreated.remove(beanName);
+		synchronized (this.mergedBeanDefinitions) {
+			this.alreadyCreated.remove(beanName);
+		}
 	}
 
 	/**