ruby-toggle-block, ruby-do-end-to-brace, ruby-brace-to-do-end and ruby-mode-set-encoding are very much present in Emacs trunk, and the first one is bound to the same key combination as in ruby-additional.
This issue was solved with changeset r43475.
Dmitry, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.
misc/ruby-additional.el: Remove functions implemented in Emacs 24.3.
misc/ruby-additional.el (ruby-brace-to-do-end)
(ruby-do-end-to-brace, ruby-toggle-block): Remove functions that
are already in the latest released version of Emacs (24.3).
[Bug #7565]