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
bool Browser::CanCloseWithInProgressDownloads() {
  if (cancel_download_confirmation_state_ != NOT_PROMPTED)
    return cancel_download_confirmation_state_ != WAITING_FOR_RESPONSE;

  int num_downloads_blocking;
  if (DOWNLOAD_CLOSE_OK ==
      OkToCloseWithInProgressDownloads(&num_downloads_blocking))
    return true;

  cancel_download_confirmation_state_ = WAITING_FOR_RESPONSE;
  window_->ConfirmBrowserCloseWithPendingDownloads();

  return false;
}

bool Browser::CanCloseWithInProgressDownloads() {
  if (cancel_download_confirmation_state_ != NOT_PROMPTED)
    return cancel_download_confirmation_state_ != WAITING_FOR_RESPONSE;

  int num_downloads_blocking;
  if (DOWNLOAD_CLOSE_OK ==
      OkToCloseWithInProgressDownloads(&num_downloads_blocking))
    return true;

  cancel_download_confirmation_state_ = WAITING_FOR_RESPONSE;
  window_->ConfirmBrowserCloseWithPendingDownloads();

  return false;
}
