Remove TabContents from TabStripModelObserver::TabDetachedAt.

BUG=107201
TEST=no visible change


Review URL: https://chromiumcodereview.appspot.com/11293205

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@167122 0039d316-1c4b-4281-b951-d872f2087c98
RendererProcessClosedObserver::RendererProcessClosedObserver(
    AutomationProvider* automation,
    IPC::Message* reply_message)
    : automation_(automation->AsWeakPtr()),
      reply_message_(reply_message) {
  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
                 content::NotificationService::AllSources());
}

RendererProcessClosedObserver::RendererProcessClosedObserver(
    AutomationProvider* automation,
    IPC::Message* reply_message)
    : automation_(automation->AsWeakPtr()),
      reply_message_(reply_message) {
  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
                 content::NotificationService::AllSources());
}
