Update Hierarchical container JavaDocs to match code (#5864)

Change-Id: Iaac3c77d80f950c683841264c4907340278354a6

diff --git a/compatibility-server/src/main/java/com/vaadin/v7/data/Container.java b/compatibility-server/src/main/java/com/vaadin/v7/data/Container.java
index 5a73d360e4e893230d5fff290ebd89afeabb201b..cffd2463983adfa13b050e6b01274039649d192f 100644 (file)
--- a/compatibility-server/src/main/java/com/vaadin/v7/data/Container.java
+++ b/compatibility-server/src/main/java/com/vaadin/v7/data/Container.java
@@ -672,7 +672,8 @@ public interface Container extends Serializable {
          *            ID of the Item whose children the caller is interested in
          * @return An unmodifiable {@link java.util.Collection collection}
          *         containing the IDs of all other Items that are children in
-         *         the container hierarchy
+         *         the container hierarchy; {@code null} if item does not have
+         *         any children.
          */
         public Collection<?> getChildren(Object itemId);