There are some, myself included, who believe many of the “mainstream” projects are only open to avoid antitrust lawsuits in America. The reason why there is chromium vs chrome and AOSP Android vs Google Android, is to take advantage of the confusion to make it sound as if the actual Google product is open source, where as the Google product is based upon the open source project. This makes it sound like anybody could copy Google’s product and give them a run for their money, which is obviously not the case.