Compaq did not release their own API. They released their own implementation of IBM's BIOS API. The cleanroom part was the implementation of the BIOS API's, not the API's themselves. The API was identical to IBM's otherwise the Compaq BIOS would have been useless.
If Google, or anyone else, implements an existing Java API, it must have identical definitions otherwise it won't work. Your argument is silly. You could easily determine the API by simply looking at any Java program which used it. And that program could be under any license, including public domain.
Also, I can certainly create audio CDs without ever purchasing the Red Book. Copyright only protects the book itself, not the knowledge it contains. That knowledge can be gotten legally in any number of ways, including simply reading the source of a program which implements CD audio creation.