INT-3580: Polishing to the last STOMP tests fix

JIRA: https://jira.spring.io/browse/INT-3580

* Uncomment `org.springframework.integration.ip` category for the IP tests `log4j.properties`
* Since all tests in the `StompIntegrationTests` uses the same application context and therefore the same `SubscriptionRegistry`
the `waitForSubscribe()` should wait exactly for that `subscription` in which it is interested in.
The previous fix wasn't enough

spring-integration-ip/src/test/resources/log4j.properties

@@ -5,4 +5,4 @@ log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
 log4j.appender.stdout.layout.ConversionPattern=%d %c{1} [%t] : %m%n
 
 log4j.category.org.springframework.integration=WARN
-#log4j.category.org.springframework.integration.ip=WARN
+log4j.category.org.springframework.integration.ip=WARN

spring-integration-websocket/src/test/java/org/springframework/integration/websocket/client/StompIntegrationTests.java

@@ -135,7 +135,7 @@ public class StompIntegrationTests {
 
 		this.webSocketOutputChannel.send(message);
 
-		waitForSubscribe();
+		waitForSubscribe("increment");
 
 		this.webSocketOutputChannel.send(message2);
 
@@ -161,7 +161,7 @@ public class StompIntegrationTests {
 
 		this.webSocketOutputChannel.send(message);
 
-		waitForSubscribe();
+		waitForSubscribe("foo");
 
 		this.webSocketOutputChannel.send(message2);
 
@@ -215,7 +215,7 @@ public class StompIntegrationTests {
 
 		this.webSocketOutputChannel.send(message);
 
-		waitForSubscribe();
+		waitForSubscribe("error");
 
 		this.webSocketOutputChannel.send(message2);
 
@@ -248,7 +248,7 @@ public class StompIntegrationTests {
 
 		this.webSocketOutputChannel.send(message);
 
-		waitForSubscribe();
+		waitForSubscribe("answer");
 
 		this.webSocketOutputChannel.send(message2);
 
@@ -257,25 +257,33 @@ public class StompIntegrationTests {
 		assertEquals("Hello Bob", receive.getPayload());
 	}
 
-	private void waitForSubscribe() throws InterruptedException {
+	private void waitForSubscribe(String destination) throws InterruptedException {
 		SimpleBrokerMessageHandler serverBrokerMessageHandler =
 				this.serverContext.getBean("simpleBrokerMessageHandler", SimpleBrokerMessageHandler.class);
 
 		SubscriptionRegistry subscriptionRegistry = serverBrokerMessageHandler.getSubscriptionRegistry();
 
-		@SuppressWarnings("rawtypes")
-		Map subscriptions = TestUtils.getPropertyValue(subscriptionRegistry, "subscriptionRegistry.sessions", Map.class);
-
 		int n = 0;
-
-		while (subscriptions.isEmpty() && n++ < 100) {
+		while (!containsDestination(destination, subscriptionRegistry) && n++ < 100) {
 			Thread.sleep(100);
-			subscriptions = TestUtils.getPropertyValue(subscriptionRegistry, "subscriptionRegistry.sessions", Map.class);
 		}
 
-		assertTrue("The subscription for the 'user/queue/error' hasn't been registered", n < 100);
+		assertTrue("The subscription for the '" + destination + "' destination hasn't been registered", n < 100);
 	}
 
+	@SuppressWarnings("rawtypes")
+	private boolean containsDestination(String destination, SubscriptionRegistry subscriptionRegistry) {
+		Map sessions = TestUtils.getPropertyValue(subscriptionRegistry, "subscriptionRegistry.sessions", Map.class);
+		for (Object info : sessions.values()) {
+			Map subscriptions = TestUtils.getPropertyValue(info, "subscriptions", Map.class);
+			for (Object dest : subscriptions.keySet()) {
+				if (((String) dest).contains(destination)) {
+					return true;
+				}
+			}
+		}
+		return false;
+	}
 
 	@Configuration
 	@EnableIntegration