Writing your own rendering engine that works exactly like chrome, has the same features and preferably no exploits is not something you or even a big company can whack out in a week or so. You need to support js, css, html, hardware acceleration, https, certificate checks, support notifications, location, camera and mic, video play and a whole lot of other features you take for granted. A modern browser is light years away from the first browsers that came out around 2000.