https://bugs.webkit.org/show_bug.cgi?id=29170

Reviewed by Maciej Stachowiak.

This patch basically requires two separate steps, the first is to split getPropertyNames
into two functions -- getOwnPropertyNames and getPropertyNames, basically making them behave
in the same way as getOwnPropertySlot and getPropertySlot.  In essence getOwnPropertyNames
produces the list of properties on an object excluding its prototype chain and getPropertyNames
just iterates the the object and its prototype chain calling getOwnPropertyNames at each level.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@48336 268f45cc-cd09-0410-ab3c-d52691b4dbfc