Revert the UseCounter for HTMLPreElement.width

This was missing from the multipage spec because of a bug:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=26475

There's no point in measuring usage as it's per spec.

Review URL: https://codereview.chromium.org/449643003

git-svn-id: svn://svn.chromium.org/blink/trunk@179696 bbb929c8-8fbe-4397-9dbb-9b2b20218538