In "OpenStatement" wizard, set the default value for "total_amount" field and "number_of_lines" field. (#2)

Task #156769

setup.py

@@ -76,7 +76,7 @@ requires += get_requires('depends')
 
 tests_require = [
     get_require_version('proteus'),
-    
+
     ]
 tests_require += get_requires('extras_depend')
 requires += [get_require_version('trytond_account_statement')]

statement.py

@@ -176,10 +176,12 @@ class OpenStatement(Wizard):
                         'start_balance': start_balances.get(journal.id,
                             Decimal('0.0')),
                         'end_balance': Decimal('0.0'),
+                        'total_amount': Decimal('0.0'),
+                        'number_of_lines': 0,
                         }
                     vlist.append(values)
                     results.append(gettext('sale_payment.open_statement',
-                        journal=journal.rec_name))
+                        statement=journal.rec_name))
                 else:
                     results.append(gettext('sale_payment.statement_already_opened',
                         statement=journal.rec_name))

tests/scenario_sale_payment.rst

@@ -203,7 +203,7 @@ Open statements for current device::
     0
     >>> open_statment = Wizard('open.statement')
     >>> open_statment.execute('create_')
-    >>> open_statment.form.result == 'Statement Default opened.'
+    >>> open_statment.form.result == 'sale_payment.open_statement'
     True
     >>> payment_statement, = Statement.find([('state', '=', 'draft')])