Impacted versions:
- 8.0

Steps to reproduce:
1. open Accounting / Configuration / Taxes / Tax Codes
2. open any Tax Code
3. press Print / Account Tax

Current behavior:

QWebException: "chart_tax_id" while evaluating
"get_lines(data['form']['based_on'], data['form']['company_id'], data['form']['chart_tax_id'])"
Details: http://paste.ubuntu.com/12689915/

Expected behavior:
- Tax Code report

Test on:
- different 8.0 instances
- runbot: http://105817-8-0-6b6d73.runbot8.odoo.com/web

addons/account/report/report_vat.py
return self.pool.get('res.company').browse(self.cr, self.uid, form['company_id'], context=context).currency_id.name
    def sort_result(self, accounts, context=None):
        
        result_accounts = []
        ind=0
        old_level=0
        while ind<len(accounts):
            #
            account_elem = accounts[ind]
            #
            #