consistent converting and escaping of label values (following AbstractMultiCheckedElementTag's SPR-7174)

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/tags/form/AbstractSingleCheckedElementTag.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * Copyright 2002-2010 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -90,7 +90,7 @@ public abstract class AbstractSingleCheckedElementTag extends AbstractCheckedEle
 		if (resolvedLabel != null) {
 			tagWriter.startTag("label");
 			tagWriter.writeAttribute("for", id);
-			tagWriter.appendValue(resolvedLabel.toString());
+			tagWriter.appendValue(convertToDisplayString(resolvedLabel));
 			tagWriter.endTag();
 		}