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 TabStripModel::IsNewTabAtEndOfTabStrip(TabContents* contents) const {
  const GURL& url = contents->web_contents()->GetURL();
  return url.SchemeIs(chrome::kChromeUIScheme) &&
         url.host() == chrome::kChromeUINewTabHost &&
         contents == GetTabContentsAtImpl(count() - 1) &&
         contents->web_contents()->GetController().GetEntryCount() == 1;
}

bool TabStripModel::IsNewTabAtEndOfTabStrip(TabContents* contents) const {
  const GURL& url = contents->web_contents()->GetURL();
  return url.SchemeIs(chrome::kChromeUIScheme) &&
         url.host() == chrome::kChromeUINewTabHost &&
         contents == GetTabContentsAtImpl(count() - 1) &&
         contents->web_contents()->GetController().GetEntryCount() == 1;
}
