If the "structure, sequence, and organization" of APIs is a copyrightable work in its own right, then couldn't Google make a GPL-licensed derivative SSO (Android's API) but put their implementation under a separate license? Has anyone done a legal analysis of how the GPL's copyleft provisions would apply to this new kind of copyrighted work?
FYI, Classpath exception does not remove GPL from OpenJDK, or enable anyone to create a non-GPL JDK. It allows you to create Java programs that are themselves not GPL.