In order to provide an integrated support for various revision control systems, Designer uses the Eclipse Team Provider plugins. Plugins are available for most revision control systems from marketplace.eclipse.org. Here are links for several of the more common/popular plugins:
Subversion svn Plugin: http://marketplace.eclipse.org/content/subversive-svn-team-provider
Mercurial hg Plugin: http://marketplace.eclipse.org/content/mercurialeclipse-was-hgeclipse
GIT egit Plugin: http://marketplace.eclipse.org/content/egit-git-team-provider
Perforce p4 Plugin: http://www.perforce.com/product/components/eclipse_plugin