Reviewed by Maciej.

    Reviewed by Maciej.

        - fix a failure seen in the Mozilla JavaScript tests where a live object was garbage-collected
          when the only reference to it was in an argList on the stack

        * kjs/list.h: Moved the operator= function into the .cpp file since it's too big to be
        a good choice to inline.
        * kjs/list.cpp: (KJS::List::operator=): Moved this formerly-inline function into a separate
        file and added missing code to update valueRefCount. It's the latter that fixes the bug.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@9179 268f45cc-cd09-0410-ab3c-d52691b4dbfc