Fix detection of |handle_smi| case in HOptimizedGraphBuilder::HandlePolymorphicCallNamed

BUG=chromium:196583

Review URL: https://codereview.chromium.org/12620014

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@13963 ce2b1a6d-e550-0410-aec6-3dcde31c8c00