By using the lexCss("color:") to measure the performance
The change make the lexCss("color:")
  x21 - x40 times faster than trunk.
  x2.3 - x4.6 times faster than m74.

Design Doc: http://shorturl.at/adfO5

Measured by out/x64.release/d8 reg977003.js
see reg977003.js attached to chromium:977003

Also see another cl of benchmark in
https://chromium-review.googlesource.com/c/v8/v8/+/1679651/


Bug: chromium:977003
Change-Id: Ie8518493d2c33df1594be1b4576bda715087b421
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1674851
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62471}