How do I restore the colon to the Google keyboard suggested punctuation?

[AC Question]

Since my last Android update (to Marshmallow/6.0), the Google keyboard has changed. I prefer to have the auto suggestion provide punctuation instead of next word prediction. In all prior versions, pressing space would result in suggesting {? ! : ;} and now it only offers {? ! and ;}. How do I get the colon to appear there?