message: Fix the bug of charts/slices cannot be filtered by datasource name.
diff: @@ -1189,7 +1189,8 @@ class Superset(BaseSupersetView):
  slice_overwrite_perm,
  slice_download_perm,
  datasource_id,
  - datasource_type)
  + datasource_type,
  + datasource.name)
  form_data['datasource'] = str(datasource_id) + '__' + datasource_type
  @@ -1255,7 +1256,7 @@ class Superset(BaseSupersetView):
  def save_or_overwrite_slice(
  self, args, slc, slice_add_perm, slice_overwrite_perm, slice_download_perm,
  - datasource_id, datasource_type):
  + datasource_id, datasource_type, datasource_name):
  """Save or overwrite a slice"""
  slice_name = args.get('slice_name')
  action = args.get('action')
  @@ -1267,7 +1268,7 @@ class Superset(BaseSupersetView):
  slc = models.Slice(owners=[g.user] if g.user else [])
  slc.params = json.dumps(form_data)
  - slc.datasource_name = args.get('datasource_name')
  + slc.datasource_name = datasource_name
  slc.viz_type = form_data['viz_type']
  slc.datasource_type = datasource_type
  slc.datasource_id = datasource_id
  