Bug 620988 - preferences code uses getFolderContents but never closes the container.

r+a=gavin

browser/components/preferences/selectBookmark.js

@@ -103,6 +103,7 @@ var SelectBookmarkDialog = {
           names.push(node.title);
         }
       }
+      contents.containerOpen = false;
     }
     else {
       urls.push(selectedNode.uri);