Bug 1616901 - Remove accidental print statements. r=jrmuizel
Bug 1616901 - Remove accidental print statements. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D68171

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/7b36a0458e5005380fc53ca1f53978009cd609b9

servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender