cubicweb #2502646 KeyError: None res['source'] = self._cw.source_defs()[res.pop('asource')] [deprecated]

While trying to look at Entities Tab on schema visualisation as admin

Traceback (most recent call last):
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/ajaxcontroller.py", line 143, in publish
  result = func(*args)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/ajaxcontroller.py", line 284, in __call__
  return self.serialize(implementation(self, *args, **kwargs))
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/ajaxcontroller.py", line 375, in view
  return self._call_view(viewobj, paginate=req.form.pop('paginate', False))
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/ajaxcontroller.py", line 246, in _call_view
  view.render(**kwargs)
File "/usr/lib/python2.6/dist-packages/cubicweb/view.py", line 176, in render
  view_func(**context)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/schema.py", line 177, in call
  'Any X ORDERBY N WHERE X is CWEType, X name N, X final FALSE'))
File "/usr/lib/python2.6/dist-packages/cubicweb/view.py", line 282, in wview
  self._cw.view(__vid, rset, __fallback_vid, w=self.w, **kwargs)
File "/usr/lib/python2.6/dist-packages/cubicweb/req.py", line 348, in view
  return view.render(w=w, **kwargs)
File "/usr/lib/python2.6/dist-packages/cubicweb/view.py", line 176, in render
  view_func(**context)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 623, in call
  self.layout_render(self.w)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/component.py", line 274, in layout_render
  layout.render(w)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 208, in render
  self.render_table(w, actions, self.view.paginable)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 249, in render_table
  self.render_table_body(w, colrenderers)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 228, in render_table_body
  self.render_row(w, rownum, colrenderers)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 264, in render_row
  self.render_cell(w, rownum, colnum, renderer)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 279, in render_cell
  renderer.render_cell(w, rownum)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/tableview.py", line 521, in render_cell
  row=rownum, col=self.colid, w=w)
File "/usr/lib/python2.6/dist-packages/cubicweb/req.py", line 348, in view
  return view.render(w=w, **kwargs)
File "/usr/lib/python2.6/dist-packages/cubicweb/view.py", line 176, in render
  view_func(**context)
File "/usr/lib/python2.6/dist-packages/cubicweb/web/views/baseviews.py", line 170, in cell_call
  xml_escape(entity.absolute_url()), xml_escape(desc),
File "/usr/lib/python2.6/dist-packages/cubicweb/entity.py", line 621, in absolute_url
  sourcemeta = self.cw_metainformation()['source']
File "/usr/lib/pymodules/python2.6/logilab/common/decorators.py", line 65, in wrapped
  return self.__call__(*args, **kwargs)
File "/usr/lib/pymodules/python2.6/logilab/common/decorators.py", line 59, in __call__
  value = __me.callable(self, *args)
File "/usr/lib/python2.6/dist-packages/cubicweb/entity.py", line 586, in cw_metainformation
  res['source'] = self._cw.source_defs()[res.pop('asource')]
KeyError: None
prioritynormal
typebug
done in<not specified>
load0.000
load left0.000
closed by<not specified>