There is a new spell for Resto Druids in the 5.4 PTR, called Genesis. This is not exactly a cooldown per se, but it could definitely be seen that way since it can easily be used at periods of intense damage to heal more quickly.
Targets all party or raid members within 60 yards and accelerates the caster’s Rejuvenation effects, causing them to heal and expire at 400% of the normal rate.
The spell uses 14.5% base mana, but what is unusual about this is that there is currently no CD associated with this spell.
There was some confusion about this spell and whether it was for Priests or Druids, since it also stated “Can be cast in Spirit of Redemption; Can’t be cast in Shadowform” originally. This has been removed now, but it could have somehow started as a spell by the same name for priests that never made it in the game.