chore(React 16): switch onClick prop to new API
chore(React 16): switch onClick prop to new API

rlr/activity-streams,Mardak/activity-stream,sarracini/activity-stream,Mardak/activity-stream,AdamHillier/activity-stream,mozilla/activity-stream,mozilla/activity-streams,Mardak/activity-stream,AdamHillier/activity-stream,mozilla/activity-stream,sarracini/activity-stream,Mardak/activity-stream,mozilla/activity-stream,rlr/activity-streams,mozilla/activity-stream,AdamHillier/activity-stream,mozilla/activity-streams,sarracini/activity-stream,AdamHillier/activity-stream,sarracini/activity-stream,rlr/activity-streams,rlr/activity-streams