Make scrollbar look like Chrome/Chromium

[ItsKruistz]

I think a scrollbar like these images would look better, i see Adapta theme have that then why not for Materia?
Screenshot in Chrome browser

There are the screenshot of a scrollbar in Adapta theme:

But in Materia theme it looks kinda... kinda Gnomish. It would look more like Material Design if the scrollbar is styled to look like that.

[intrnl]

Chrome follows the OS for scrollbar, except on Linux where it uses Windows' instead, so it's not really representative of Material Design.

Gnome's overlay scrollbars are pretty close already