Reviewed by Dave Hyatt.

        - fix http://bugs.webkit.org/show_bug.cgi?id=13037
          REGRESSION: Copy-on-scroll not reset properly after back/forward navigation

        * page/FrameView.cpp:
        (WebCore::FrameViewPrivate::FrameViewPrivate): Moved initialization of
        m_slowRepaintObjectCount here.
        (WebCore::FrameViewPrivate::reset): Do not reset the slow repaint object
        count here.
        (WebCore::FrameView::useSlowRepaints):
        (WebCore::FrameView::addSlowRepaintObject):
        (WebCore::FrameView::removeSlowRepaintObject): Added an assertion that the
        object count is positive.
        * rendering/RenderObject.cpp:
        (WebCore::RenderObject::setStyle): Corrected a mix up between old and new
        style, which caused the object count to be decremented when it was supposed
        to be incremented and vice versa.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@21329 268f45cc-cd09-0410-ab3c-d52691b4dbfc