load_lang was a kind of hybrid method trying to active or creating a
language if not found. This was error prone.
Instead rely on two methods with clear purpose:
ResLang._create_lang(lang, lang_name=None)
- create a new res.lang entry using the locale of the server
return the res.lang record to match the API of _activate_lang
ResLang._active_lang(code)
- activate the given code lang
Most of the time, _active_lang is what is expected
tools.trans_load_data and IrTranslation._load_module_terms no longer
activate the language if not active.
Loading the translations should be explicit on an activated language,
it is too error prone to silently activate/create a language if not
found.
Remove lang_name from trans_load_data as no longer needed.
Martin Trigaux
49fbab5329