One could, but the Chromium sourcecode provided by Google is a quickly moving target. So your patch will need to be updated very often. Distro maintainers are a

One could, but the Chromium sourcecode provided by Google is a quickly moving target. So your patch will need to be updated very often. Distro maintainers are already complaining about Chromium being a lot of work because of the rate of change and build breakage. A patch will make that worse. Also, I would bet Google would do a few "neccessary" changes in the bookmark parts over the next releases, just to make your patch not work.