Chromebooks have a reputation as low-power, low-cost machines. That isn't always true, but up to now there hasn't been much reason to push them out of that broad category. Reports indicated that at least one new model coming down the pipe will arrive with a dedicated graphics card, something that the platform has been lacking so far.
Chrome Unboxed reports finding unused code in Chromium referring to a device with the codename "Mushu," a variant of the Hatch device tree. According to them, the Mushu is running a combination of a 10th-generation Intel Core processor and an AMD Vega 12 graphics card. The Vega 12 discrete GPU has been rumored as of 2018 (matching the slightly older CPU architecture), but has yet to actually be released, either as a desktop GPU or a laptop card. A desktop version did pop up on eBay for a short time.
Vega 12's hardware indicates that it's on the lower end of things, a small step up from the Vega series of integrated GPUs (which are, it has to be said, a lot more powerful than the word "integrated" might make you think). Of course, there's no guarantee that the Mushu device will actually make its way from codename to retail product, and there's not much in terms of Chrome-compatible games to take advantage of it, unless Valve finally gets around to building Steam for Chrome OS.
The achingly slow progress on that front might explain why we're seeing commits for a device with a processor and discrete GPU that are considerably behind the cutting edge. Keep your fingers crossed.