INT-1715 fixed poller schema definition to allow 'ref' attribute on inner-pollers definitions used in non-core schemas

spring-integration-core/src/test/java/org/springframework/integration/config/xml/PollerParserTests.java

@@ -35,6 +35,7 @@ import org.springframework.scheduling.support.PeriodicTrigger;
 
 /**
  * @author Mark Fisher
+ * @author Oleg Zhurakousky
  */
 public class PollerParserTests {
 
@@ -111,4 +112,10 @@ public class PollerParserTests {
 		new ClassPathXmlApplicationContext(
 				"cronTriggerWithTimeUnit-fail.xml", PollerParserTests.class);
 	}
+    
+    @Test(expected=BeanDefinitionParsingException.class)
+	public void topLevelPollerWithRef() {
+		new ClassPathXmlApplicationContext(
+				"defaultPollerWithRef.xml", PollerParserTests.class);
+	}
 }

spring-integration-core/src/test/java/org/springframework/integration/config/xml/defaultPollerWithRef.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans:beans xmlns="http://www.springframework.org/schema/integration"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:beans="http://www.springframework.org/schema/beans"
+	xsi:schemaLocation="http://www.springframework.org/schema/beans
+			http://www.springframework.org/schema/beans/spring-beans.xsd
+			http://www.springframework.org/schema/integration
+			http://www.springframework.org/schema/integration/spring-integration-2.0.xsd">
+
+	<poller id="defaultPollerWithId" default="true" fixed-rate="5000"/>
+		
+	<poller id="defaultPollerWithRef" ref="defaultPollerWithId"/>
+	
+</beans:beans>