Remove unused condition filter in StyleBuilder template

The condition variable never gets set, so no point filtering with it.

BUG=237400

Review URL: https://codereview.chromium.org/262173005

git-svn-id: svn://svn.chromium.org/blink/trunk@173360 bbb929c8-8fbe-4397-9dbb-9b2b20218538