message: Fix toggle for email notifications
  The function doesn't receive an event, it receives a boolean.
  Fixes
diff: @@ -132,9 +132,9 @@ module.exports = React.createClass({
  });
  },
  - onEnableEmailNotificationsChange: function(address, event) {
  + onEnableEmailNotificationsChange: function(address, checked) {
  let emailPusherPromise;
  - if (event.target.checked) {
  + if (checked) {
  const data = {};
  data['brand'] = SdkConfig.get().brand || 'Riot';
  emailPusherPromise = UserSettingsStore.addEmailPusher(address, data);
  