This tests that the toString() function does not enumerate.

PASS: the toString function is not enumerable for HTMLAnchorElement.
PASS: the toString function is not enumerable for Location.
PASS: the toString function is not enumerable for Selection.
PASS: the toString function is not enumerable for HTMLDivElement.
PASS: the toString function is not enumerable for HTMLDocument.
PASS: the toString function is not enumerable for Object.
PASS: the toString function is not enumerable for Array.