I think that link is just outdated, it doesn't mention ICS at all.

The link for this submission says:

"This release includes the full history of the Android source code tree, which naturally includes all the source code for the Honeycomb releases. However, since Honeycomb was a little incomplete, we want everyone to focus on Ice Cream Sandwich. So, we haven't created any tags that correspond to the Honeycomb releases (even though the changes are present in the history.)"

Is it possible that specific page of documentation has just not been updated yet? The linked thread has Jean-Baptiste Queru stating:

> This release includes the full history of the Android source code tree, which naturally includes all the source code for the Honeycomb releases.

From Jean-Baptiste Queru's announcement

http://groups.google.com/group/android-building/msg/c0e01b46...

I gather that the "complete" Honeycomb source is available as part of the git history, but without tags.