The traverseTo(key, options)
method steps are:
If this's current entry
index is −1, then return an early
error result for an "InvalidStateError"
DOMException.
If this's entry list does not
contain a NavigationHistoryEntry whose session history entry's navigation
API key equals key, then return an early error result for an
"InvalidStateError" DOMException.
Return the result of performing a navigation API traversal given this, key, and options.