[REF] core: ConfigCleaner(6) load keys via the index

This commit is part of a larger refactor, see associated PR.

Using the new `cli_loadable` and `file_loadable` attributes, it is
possible to list all keys that were defined in the hardcoded listing.

The difference are `pg_path` and `test_enable` that were not present in
the previous listing but present in the new comprehension:

* for pg_path, it was set just bellow using the same cli->file fallback
  logic

* for test_enable, its value is reset on `bool(test_tags)` anyway...

The previous code was using two (almost) identical loops with two
hardcoded listing. The two loops were at first difference but d5e7247
made them basically identical, almost 10 years ago.

odoo/tools/config.py

@@ -482,17 +482,11 @@ def die(cond, msg):
         if self.options['server_wide_modules'] in ('', 'None', 'False'):
             self.options['server_wide_modules'] = 'base,web'
 
-        # if defined do not take the configfile value even if the defined value is None
-        keys = ['gevent_port', 'http_interface', 'http_port', 'longpolling_port', 'http_enable', 'x_sendfile',
-                'db_name', 'db_user', 'db_password', 'db_host', 'db_sslmode',
-                'db_port', 'db_template', 'logfile', 'pidfile', 'smtp_port',
-                'email_from', 'smtp_server', 'smtp_user', 'smtp_password', 'from_filter',
-                'smtp_ssl_certificate_filename', 'smtp_ssl_private_key_filename',
-                'db_maxconn', 'db_maxconn_gevent', 'import_partial', 'addons_path', 'upgrade_path',
-                'syslog', 'without_demo', 'screencasts', 'screenshots',
-                'dbfilter', 'log_level', 'log_db',
-                'log_db_level', 'geoip_city_db', 'geoip_country_db', 'dev_mode',
-                'shell_interface',
+        keys = [
+            option_name for option_name, option
+            in self.options_index.items()
+            if option.cli_loadable and option.file_loadable
+            if option.action != 'append'
         ]
 
         for arg in keys:
@@ -508,37 +502,6 @@ def die(cond, msg):
             self.options['log_handler'] = self.options['log_handler'].split(',')
         self.options['log_handler'].extend(opt.log_handler)
 
-        # if defined but None take the configfile value
-        keys = [
-            'language', 'translate_out', 'translate_in', 'overwrite_existing_translations',
-            'dev_mode', 'shell_interface', 'smtp_ssl', 'load_language',
-            'stop_after_init', 'without_demo', 'http_enable', 'syslog',
-            'list_db', 'proxy_mode',
-            'test_file', 'test_tags',
-            'osv_memory_count_limit', 'transient_age_limit', 'max_cron_threads', 'unaccent',
-            'data_dir',
-            'server_wide_modules',
-        ]
-
-        posix_keys = [
-            'workers',
-            'limit_memory_hard', 'limit_memory_soft',
-            'limit_time_cpu', 'limit_time_real', 'limit_request', 'limit_time_real_cron'
-        ]
-
-        if os.name == 'posix':
-            keys += posix_keys
-        else:
-            self.options.update(dict.fromkeys(posix_keys, None))
-
-        # Copy the command-line arguments...
-        for arg in keys:
-            if getattr(opt, arg) is not None:
-                self.options[arg] = getattr(opt, arg)
-            # ... or keep, but cast, the config file value.
-            elif isinstance(self.options[arg], str) and self.casts[arg].type in optparse.Option.TYPE_CHECKER:
-                self.options[arg] = optparse.Option.TYPE_CHECKER[self.casts[arg].type](self.casts[arg], arg, self.options[arg])
-
         ismultidb = ',' in (self.options.get('db_name') or '')
         die(ismultidb and (opt.init or opt.update), "Cannot use -i/--init or -u/--update with multiple databases in the -d/--database/db_name")
 
@@ -573,9 +536,6 @@ def die(cond, msg):
         dev_split = [s.strip() for s in opt.dev_mode.split(',')] if opt.dev_mode else []
         self.options['dev_mode'] = dev_split + (['reload', 'qweb', 'xml'] if 'all' in dev_split else [])
 
-        if opt.pg_path:
-            self.options['pg_path'] = opt.pg_path
-
         self.options['test_enable'] = bool(self.options['test_tags'])
 
         if self.options['longpolling_port']: