DevTools: added Text Autosize record type to Timeline

Add InspectorInstrumentation::{will,did}AutosizeText and "Autosize Text"
timeline record.

BUG=302892

Review URL: https://codereview.chromium.org/27478002

git-svn-id: svn://svn.chromium.org/blink/trunk@159974 bbb929c8-8fbe-4397-9dbb-9b2b20218538