Store Drupal 7 webforms in code
Not really, and there is no need for it

If you need form available from code, Form API forms are not that hard to write from scratch. Contrary to Views, you can only theme Webforms bu their node ID, and that would change from site to site, so Webform forms bundled with module will not be convenient.

If you want to bundle forms with your modules, and for any reason you can't use Form API, UUID Features Integration and Webform share provide ways to do it. It will not be a code in pure sense, but it should work.

It's relatively easy to use hook_form_alter to obtain Form API representation of particular webform. Of course, you won't be able to change it easily in future, but again, contrary to views, it is good. Module is not hurt if some data is not displayed. Data not provided, or provided in a way module does not expect, may break things. So if module needs a form, it should not be easy to edit. Edits to form would require edits to module's code anyway, so Form API code makes things easier, not harder in the long run, in such situations.