INT-4275: Add IntegrationFlowContext.getRegistry

JIRA: https://jira.spring.io/browse/INT-4275

To analyze the state of the `IntegrationFlowContext` provide the access to
its internal `registry`

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

@@ -16,6 +16,7 @@
 
 package org.springframework.integration.dsl.context;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -171,6 +172,15 @@ public final class IntegrationFlowContext implements BeanFactoryAware {
 				.getMessagingTemplate();
 	}
 
+	/**
+	 * Provide the state of the mapping of integration flow names to their
+	 * {@link IntegrationFlowRegistration} instances.
+	 * @return the registry of flow ids and their registration.
+	 */
+	public Map<String, IntegrationFlowRegistration> getRegistry() {
+		return Collections.unmodifiableMap(this.registry);
+	}
+
 	private String generateBeanName(Object instance, String parentName) {
 		if (instance instanceof NamedComponent && ((NamedComponent) instance).getComponentName() != null) {
 			return ((NamedComponent) instance).getComponentName();