[FIX] ir.mail_server: make SMTP test consistent with the rest

Simplifies the code and makes sure we are calling the connect()
method in the same way we do for normal deliveries, and that
all parameters are processed in the same fashion.

odoo/addons/base/ir/ir_mail_server.py

@@ -174,9 +174,7 @@ class IrMailServer(models.Model):
         for server in self:
             smtp = False
             try:
-                smtp = self.connect(server.smtp_host, server.smtp_port, user=server.smtp_user,
-                                    password=server.smtp_pass, encryption=server.smtp_encryption,
-                                    smtp_debug=server.smtp_debug)
+                smtp = self.connect(mail_server_id=server.id)
             except Exception as e:
                 raise UserError(_("Connection Test Failed! Here is what we got instead:\n %s") % ustr(e))
             finally:
@@ -222,7 +220,8 @@ class IrMailServer(models.Model):
             smtp_port = tools.config.get('smtp_port', 25) if port is None else port
             smtp_user = user or tools.config.get('smtp_user')
             smtp_password = password or tools.config.get('smtp_password')
-            if encryption is None and tools.config.get('smtp_ssl'):
+            smtp_encryption = encryption
+            if smtp_encryption is None and tools.config.get('smtp_ssl'):
                 smtp_encryption = 'starttls' # smtp_ssl => STARTTLS as of v7
 
         if not smtp_server: