Making instanceOf() work also for non HTML elements (elements without ownerDocument property), to avoid the use of the instanceof operator, that may cause error in other browsers when the Class is not defined in the global namespace.
Making instanceOf() work also for non HTML elements (elements without ownerDocument property), to avoid the use of the instanceof operator, that may cause error in other browsers when the Class is not defined in the global namespace.

git-svn-id: 1493d24fe73b4f776bca2921d92e98ee55d200cb@5813 e969d3be-0e28-0410-a27f-dd5c76401a8b

firebug/firebug-lite,firebug/firebug-lite,firebug/firebug-lite,firebug/firebug-lite,firebug/firebug-lite