[SPR-6004] Fixed NPE in BeanDefinitionParserDelegate when using empty namespace as the default

org.springframework.beans/src/main/java/org/springframework/beans/factory/xml/BeanDefinitionParserDelegate.java

@@ -1363,7 +1363,7 @@ public class BeanDefinitionParserDelegate {
 			if (handler != null) {
 				return handler.decorate(node, originalDef, new ParserContext(this.readerContext, this, containingBd));
 			}
-			else if (namespaceUri.startsWith("http://www.springframework.org/")) {
+			else if (namespaceUri != null && namespaceUri.startsWith("http://www.springframework.org/")) {
 				error("Unable to locate Spring NamespaceHandler for XML schema namespace [" + namespaceUri + "]", node);
 			}
 			else {