tree 3b22d10c3d1583e29aba801a63c7cc2ad6926387
parent 4638d7ab64fd31547a30a71d6356105b2c1285d5
author Craig Tiller <ctiller@google.com> 1486679132 -0800
committer Craig Tiller <ctiller@google.com> 1486679132 -0800

Make combiners refcounted, to facilitate sharing