Only enable shouldCloseWithWindow when ObjC GC is enabled.
        This maintains backwards compatibility with applications
        that expect a WebView to be usable after the window closes.

        * WebView/WebView.m:
        (-[WebViewPrivate init]):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@15110 268f45cc-cd09-0410-ab3c-d52691b4dbfc