It's not 100% MIT. Chromium's Blink renderer has LGPLv2.1 code going back to the KDE KHTML days, such as some of the code for the DOM:
https://github.com/chromium/chromium/blob/master/third_party...
Very rough way of going about it, but searching for files with copyright headers crediting KDE shows 832 files
https://github.com/chromium/chromium/search?l=C%2B%2B&q=kde....