GH-3253: Scan BF hierarchy for BeanDefinition

Fixes #3253

The `IntegrationFlowBeanPostProcessor` uses a `containsBean()`
and then `getBeanDefinition()` to be sure that we don't override already
existing bean even if it is created in the parent(s) context.
The problem that `containsBean()` check the hierarchy, but `getBeanDefinition()`
doesn't.
So, we fail with `NoSuchBeanDefinitionException` if bean exists in the parent ctx

* Introduce an utility `IntegrationContextUtils.getBeanDefinition()` to
scan `BeanFactory` recursively for `BeanDefinition` for the requested `name`
* Use this tool in the `IntegrationFlowBeanPostProcessor` logic

**Cherry-pick to 5.2.x & 5.1.x**

Author: artembilan

spring-integration-core/src/main/java/org/springframework/integration/context/IntegrationContextUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,9 @@
 import java.util.Properties;
 
 import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
+import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.expression.spel.support.SimpleEvaluationContext;
@@ -212,4 +215,26 @@ public static Properties getIntegrationProperties(BeanFactory beanFactory) {
 		return properties;
 	}
 
+	/**
+	 * Return a {@link BeanDefinition} with the given name,
+	 * obtained from the given {@link BeanFactory} or one of its parents.
+	 * @param name the bean name to return
+	 * @param beanFactory the {@link ConfigurableListableBeanFactory} to travers.
+	 * @return the {@link BeanDefinition} for a given name
+	 * @throws NoSuchBeanDefinitionException if a {@link BeanDefinition} is not found
+	 * @since 5.1.10
+	 */
+	public static BeanDefinition getBeanDefinition(String name, ConfigurableListableBeanFactory beanFactory) {
+		try {
+			return beanFactory.getBeanDefinition(name);
+		}
+		catch (NoSuchBeanDefinitionException ex) {
+			BeanFactory parentBeanFactory = beanFactory.getParentBeanFactory();
+			if (parentBeanFactory instanceof ConfigurableListableBeanFactory) {
+				return getBeanDefinition(name, (ConfigurableListableBeanFactory) parentBeanFactory);
+			}
+			throw ex;
+		}
+	}
+
 }

spring-integration-core/src/main/java/org/springframework/integration/dsl/context/IntegrationFlowBeanPostProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -57,6 +57,7 @@
 import org.springframework.integration.config.ConsumerEndpointFactoryBean;
 import org.springframework.integration.config.IntegrationConfigUtils;
 import org.springframework.integration.config.SourcePollingChannelAdapterFactoryBean;
+import org.springframework.integration.context.IntegrationContextUtils;
 import org.springframework.integration.core.MessageSource;
 import org.springframework.integration.dsl.ComponentsRegistration;
 import org.springframework.integration.dsl.ConsumerEndpointSpec;
@@ -138,7 +139,8 @@ public void afterSingletonsInstantiated() {
 		}
 	}
 
-	private Object processStandardIntegrationFlow(StandardIntegrationFlow flow, String flowBeanName) { // NOSONAR complexity
+	private Object processStandardIntegrationFlow(StandardIntegrationFlow flow, String flowBeanName) { // NOSONAR
+		// complexity
 		String flowNamePrefix = flowBeanName + ".";
 		if (this.flowContext == null) {
 			this.flowContext = this.beanFactory.getBean(IntegrationFlowContext.class);
@@ -283,7 +285,9 @@ else if (component instanceof AnnotationGatewayProxyFactoryBean) {
 					String beanNameToUse = entry.getValue();
 					if (StringUtils.hasText(beanNameToUse) &&
 							ConfigurableBeanFactory.SCOPE_PROTOTYPE.equals(
-									this.beanFactory.getBeanDefinition(beanNameToUse).getScope())) {
+									IntegrationContextUtils.getBeanDefinition(beanNameToUse, this.beanFactory)
+											.getScope())) {
+
 						this.beanFactory.initializeBean(componentToUse, beanNameToUse);
 					}
 					targetIntegrationComponents.put(component, beanNameToUse);
@@ -393,7 +397,8 @@ private boolean noBeanPresentForComponent(Object instance, String parentBeanName
 			String beanName = ((NamedComponent) instance).getBeanName();
 			if (beanName != null) {
 				if (this.beanFactory.containsBean(beanName)) {
-					BeanDefinition existingBeanDefinition = this.beanFactory.getBeanDefinition(beanName);
+					BeanDefinition existingBeanDefinition =
+							IntegrationContextUtils.getBeanDefinition(beanName, this.beanFactory);
 					if (!ConfigurableBeanFactory.SCOPE_PROTOTYPE.equals(existingBeanDefinition.getScope())
 							&& !instance.equals(this.beanFactory.getBean(beanName))) {
 
@@ -429,8 +434,8 @@ private void registerComponent(Object component, String beanName, String parentN
 
 		AbstractBeanDefinition beanDefinition =
 				BeanDefinitionBuilder.genericBeanDefinition((Class<Object>) component.getClass(), () -> component)
-				.applyCustomizers(customizers)
-				.getRawBeanDefinition();
+						.applyCustomizers(customizers)
+						.getRawBeanDefinition();
 
 		if (parentName != null && this.beanFactory.containsBeanDefinition(parentName)) {
 			AbstractBeanDefinition parentBeanDefinition =