Revert "DevTools: Improve performance of the element breadcrumbs."

This reverts r156551. This broke
inspector/elements/breadcrumb-updates.html.

TBR=aandrey@chromium.org
BUG=277431

Review URL: https://codereview.chromium.org/22929029

git-svn-id: svn://svn.chromium.org/blink/trunk@156556 bbb929c8-8fbe-4397-9dbb-9b2b20218538