Right now, creating a custom test group involves creating a new analysis task. It should be possible to create more custom test groups once the analysis task is created.
Created attachment 307790 [details] Adds the configurator to the analysis task page
Comment on attachment 307790 [details] Adds the configurator to the analysis task page rs=me
Committed r215636: <http://trac.webkit.org/changeset/215636>