DevTools: Move DOMNode.appropriateSelectorFor() into DOMPresentationUtil.

This is a preliminary refactoring for the DOM node CSS selector construction.

R=aandrey, eustas
BUG=277286

Review URL: https://codereview.chromium.org/83123002

git-svn-id: svn://svn.chromium.org/blink/trunk@162535 bbb929c8-8fbe-4397-9dbb-9b2b20218538