Get rid of unused global variables in HTMLIdentifier.cpp

Get rid of unused global variables in HTMLIdentifier.cpp. Those were passed to
HTMLIdentifier::addNames() but that method was not doing anything with it.

R=adamk

Review URL: https://codereview.chromium.org/46803005

git-svn-id: svn://svn.chromium.org/blink/trunk@161099 bbb929c8-8fbe-4397-9dbb-9b2b20218538