Update metadata for `speechinput` test

Add `warnings` about:
* The Speech Input API being deprecated in favor of the Web Speech API.
* Chrome, the only browser that implemented the Speech Input API,
  planing to deprecate and remove the related code.
Add test for the Web Speech Recognition API

Web Speech API Specification:
https://dvcs.w3.org/hg/speech-api/raw-file/tip/speechapi.html
Update metadata for `elem/ruby` & `style/scoped`