Code:  void PPB_Widget_Impl::Invalidate(const PP_Rect* dirty) {
   const PPP_Widget_Dev* widget = static_cast<const PPP_Widget_Dev*>(
       instance()->module()->GetPluginInterface(PPP_WIDGET_DEV_INTERFACE));
   if (!widget)
    return;
  ScopedResourceId resource(this);
  widget->Invalidate(instance()->pp_instance(), resource.id, dirty);
}

Vulnerability Type: DoS 
CWE ID: CWE-399
Summary: Use-after-free vulnerability in Google Chrome before 13.0.782.107 allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors related to instantiation of the Pepper plug-in.
Commit Message: Maintain a map of all resources in the resource tracker and clear instance back pointers when needed,

BUG=85808
Review URL: http://codereview.chromium.org/7196001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@89746 0039d316-1c4b-4281-b951-d872f2087c98