Javadoc: Add missing comments

Author: garydgregory

commons-vfs2-jackrabbit2/src/main/java/org/apache/commons/vfs2/provider/webdav4/Webdav4FileContentInfoFactory.java

@@ -36,6 +36,14 @@
  * @since 2.5.0
  */
 public class Webdav4FileContentInfoFactory implements FileContentInfoFactory {
+
+    /**
+     * Constructs a new instance.
+     */
+    public Webdav4FileContentInfoFactory() {
+        // empty
+    }
+
     @Override
     public FileContentInfo create(final FileContent fileContent) throws FileSystemException {
         final Webdav4FileObject file = (Webdav4FileObject) FileObjectUtils.getAbstractFileObject(fileContent.getFile());