Reviewed by Holger Freyther.

        [Qt] Windowed Plugins: Fix crash when QWebPage is deleted after QWebView.

        Fixes various sources of crashes:
        1. The PluginContainer is a child of QWebView. When the view gets deleted,
        the PluginView is not notified about the deletion of PluginContainer.
        2. QWebView destructor does not set client to 0.
        3. Sometimes pending paint events are sent after the plugin has died, so add
        a check in PluginView::setNPWindowIfNeeded.

        https://bugs.webkit.org/show_bug.cgi?id=30354

        * plugins/qt/PluginContainerQt.cpp:
        (PluginContainerQt::~PluginContainerQt):
        * plugins/qt/PluginViewQt.cpp:
        (WebCore::PluginView::setNPWindowIfNeeded):
2009-10-19  Girish Ramakrishnan  <girish@forwardbias.in>

        Reviewed by Holger Freyther.

        [Qt] Windowed Plugins: Fix crash when QWebPage is deleted after QWebView.

        Fixes various sources of crashes:
        1. The PluginContainer is a child of QWebView. When the view gets deleted,
        the PluginView is not notified about the deletion of PluginContainer.
        2. QWebView destructor does not set client to 0.
        3. Sometimes pending paint events are sent after the plugin has died, so add
        a check in PluginView::setNPWindowIfNeeded.

        https://bugs.webkit.org/show_bug.cgi?id=30354

        * Api/qwebview.cpp:
        (QWebView::~QWebView):
        * tests/qwebview/qwebview.pro:
        * tests/qwebview/tst_qwebview.cpp:
        (tst_QWebView::reusePage_data):
        (tst_QWebView::reusePage):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@49770 268f45cc-cd09-0410-ab3c-d52691b4dbfc