[FIX] account: fix crash on post() action of journal entry

This commits defines a new method 'action_post()' for 'account.move' object to call instead of 'post()' from the account.move form view.
Indeed, additional parameter ‘invoice’ of post() is considered as ‘context’ by webclient when called from button action and it is crashing badly.

TASK ID - 1860817

addons/account/models/account_move.py

@@ -303,6 +303,10 @@ class AccountMove(models.Model):
                     move.name = new_name
         return self.write({'state': 'posted'})
 
+    @api.multi
+    def action_post(self):
+        return self.post()
+
     @api.multi
     def button_cancel(self):
         for move in self:

addons/account/views/account_view.xml

@@ -1492,7 +1492,7 @@
             <field name="arch" type="xml">
                 <form string="Account Entry">
                     <header>
-                        <button name="post" states="draft" string="Post" type="object" class="oe_highlight" groups="account.group_account_invoice"/>
+                        <button name="action_post" states="draft" string="Post" type="object" class="oe_highlight" groups="account.group_account_invoice"/>
                         <button name="%(action_view_account_move_reversal)d" states="posted" string="Reverse Entry" type="action" groups="account.group_account_invoice"/>
                         <field name="state" widget="statusbar"/>
                     </header>