message: [bugfix] throw "TypeError: 'NoneType'..." when save chart to new/existing dash.
diff: @@ -1437,7 +1437,7 @@ class Superset(BaseSupersetView):
  """Save or overwrite a slice"""
  slice_name = args.get('slice_name')
  action = args.get('action')
  - form_data, _ = self.get_form_data()
  + form_data, unused_slc = self.get_form_data()
  if action in ('saveas'):
  if 'slice_id' in form_data:
  @@ -1474,7 +1474,7 @@ class Superset(BaseSupersetView):
  status=400)
  flash(
  - 'Slice [{}] was added to dashboard [{}]'.format(
  + _('Chart [{}] was added to dashboard [{}]').format(
  slc.slice_name,
  dash.dashboard_title),
  'info')
  @@ -1490,8 +1490,8 @@ class Superset(BaseSupersetView):
  dashboard_title=request.args.get('new_dashboard_name'),
  owners=[g.user] if g.user else [])
  flash(
  - 'Dashboard [{}] just got created and slice [{}] was added '
  - 'to it'.format(
  + _('Dashboard [{}] just got created and chart [{}] was added '
  + 'to it').format(
  dash.dashboard_title,
  slc.slice_name),
  'info')
  