Don't do CGContext flipping when painting subframes in WebKit1 on post-MountainLion OSes
https://bugs.webkit.org/show_bug.cgi?id=115392
<rdar://problem/13421519>

Reviewed by Beth Dakin.

Sync up with AppKit behavior changes that could cause subviews to be flipped when
painted.

* platform/mac/WidgetMac.mm:
(WebCore::Widget::paint):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149343 268f45cc-cd09-0410-ab3c-d52691b4dbfc