Improve scroll logic on data-grid
Improve scroll logic on data-grid

It's a little bit more performant to just query for the wrapper and
scroll it to the bottom, and I also think it makes the code clearer too.

Bug: chromium:1169021
Change-Id: Ie87e6b2de477c73d5e77170fd96e367dcac1a20e
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2644803
Reviewed-by: Paul Lewis <8915f5d5c39a08c5a3e8a8d7314756e4580816f9@chromium.org>
Commit-Queue: Paul Lewis <8915f5d5c39a08c5a3e8a8d7314756e4580816f9@chromium.org>
Auto-Submit: Jack Franklin <993fcadce4d04090da2fefd557a0995e7966c8d5@chromium.org>

ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend