Reland "DevTools: ensure console links are always visible"

Instead of using 'overflow-y: hidden' to hide overflow,
CSS containment rules can make sure that the element's
paint will not affect other elements.

Screenshot: https://imgur.com/a/jAWI7

This is a reland of 38391374b79c006e85e3b9c912267a8d4daaa7cc
Original change's description:
> DevTools: ensure console links are always visible
>
> - The %c style formatter will not apply to links in console
> - Messages now have 'overflow: hidden'
>
> Screenshot: https://imgur.com/a/7tAj9
>
> Bug: 798096
> Change-Id: Ifc31314cec2a286e58ebb5625348f8dfe2827d6e
> Reviewed-on: https://chromium-review.googlesource.com/849650
> Commit-Queue: Erik Luo <luoe@chromium.org>
> Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#527501}

Bug: 798096
Change-Id: I43f151a4c91e6f084c91017753c74e9cb4a7e08c
Reviewed-on: https://chromium-review.googlesource.com/854957
Commit-Queue: Erik Luo <luoe@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#528539}
4 files changed