title: Error to render compiling AST AttributeError: 'NoneType' object has no attribute
body: <p>I get the following error when I try to modify a rapport of an invoice module. I use <em>odoo 11</em> and this is the error:</p>
  
  <pre><code>File "/home/omar/odoo/odoo11/odoo/addons/base/ir/ir_qweb/qweb.py", line 272, in render
      self.compile(template, options)(self, body.append, values or {})
    File "/home/omar/odoo/odoo11/odoo/addons/base/ir/ir_qweb/qweb.py", line 345, in _compiled_fn
      raise e
    File "/home/omar/odoo/odoo11/odoo/addons/base/ir/ir_qweb/qweb.py", line 343, in _compiled_fn
      return compiled(self, append, new, options, log)
    File "&lt;template&gt;", line 1, in template_562_2862
    File "&lt;template&gt;", line 2, in body_call_content_2861
    File "&lt;template&gt;", line 3, in foreach_2860
    File "/home/omar/odoo/odoo11/odoo/addons/base/ir/ir_qweb/qweb.py", line 350, in _compiled_fn
      raise QWebException("Error to render compiling AST", e, path, node and etree.tostring(node[0], encoding='unicode'), name)
  odoo.addons.base.ir.ir_qweb.qweb.QWebException: 'NoneType' object has no attribute 'caseacocher'
  Traceback (most recent call last):
    File "/home/omar/odoo/odoo11/odoo/addons/base/ir/ir_qweb/qweb.py", line 343, in _compiled_fn
      return compiled(self, append, new, options, log)
    File "&lt;template&gt;", line 1, in template_account_report_invoice_document_with_payments_2933
    File "&lt;template&gt;", line 2, in body_call_content_2932
    File "&lt;template&gt;", line 82, in foreach_2896
  AttributeError: 'NoneType' object has no attribute 'caseacocher'
  
  Error to render compiling AST
  AttributeError: 'NoneType' object has no attribute 'caseacocher'
  Template: account.report_invoice_document_with_payments
  </code></pre>