
PASS Construct a TreeWalker by document.createTreeWalker(root).
PASS Construct a TreeWalker by document.createTreeWalker(root, null, null).
PASS Construct a TreeWalker by document.createTreeWalker(root, undefined, undefined).
PASS Give an invalid root node to document.createTreeWalker().
PASS Walk over nodes.
PASS Optional arguments to createTreeWalker should be optional (3 passed, null).
This test checks the basic functionality of TreeWalker.