Assume I own some open source project with no license information. Furthermore, assume nobody has contributed publicly yet and so I own the project's source code and copyright.

1. Say the source code is already hosted online. If I decide to give it an open source license by uploading the associated COPYING document to the repository and adjusting the source files accordingly, will the previous versions of the project become licensed as well? Or will the current and future versions be protected while previous versions fall under public domain?
2. Alternatively, say I start a new project using a DVCS (e.g. Mercurial) on my local machine. I commit all my changes (locally) and then add license information in a later changeset. If I were to host the project/repository, will the entire history be licensed or only the versions following that changeset?

In (2), the project is initially not hosted so this does not seem like a problem. But once it's uploaded, some of the project's history will not include the license information, making the result look almost exactly like (1).

I ask because Google Code allows you to select a license on a new project, even if you intend to import the repository afterward, making licensing seem somewhat external to the actual source code, whereas bitbucket.org does not.