void DumpRenderTreeSupportQt::overwritePluginDirectories()
{
    PluginDatabase* db = PluginDatabase::installedPlugins(/* populate */ false);

    Vector<String> paths;
    String qtPath(qgetenv("QTWEBKIT_PLUGIN_PATH").data());
    qtPath.split(UChar(':'), /* allowEmptyEntries */ false, paths);

    db->setPluginDirectories(paths);
    db->refresh();
}
void PluginData::refresh()
{
    PluginDatabase *db = PluginDatabase::installedPlugins();
    db->refresh();
}