Removed dataSource null validation

Author: sheriumair

config/src/main/java/org/springframework/security/config/authentication/JdbcUserServiceBeanDefinitionParser.java

@@ -42,14 +42,7 @@ protected String getBeanClassName(Element element) {
 	@Override
 	protected void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
 		String dataSource = element.getAttribute(ATT_DATA_SOURCE);
-		if (dataSource != null) {
-			builder.addPropertyReference("dataSource", dataSource);
-		}
-		else {
-			parserContext.getReaderContext()
-				.error(ATT_DATA_SOURCE + " is required for " + Elements.JDBC_USER_SERVICE,
-						parserContext.extractSource(element));
-		}
+		builder.addPropertyReference("dataSource", dataSource);
 		String usersQuery = element.getAttribute(ATT_USERS_BY_USERNAME_QUERY);
 		String authoritiesQuery = element.getAttribute(ATT_AUTHORITIES_BY_USERNAME_QUERY);
 		String groupAuthoritiesQuery = element.getAttribute(ATT_GROUP_AUTHORITIES_QUERY);