[fix] mail: status tracking messages are not translated into user's lang...

...uage while updating any document i.e. confitming sales or invoice, context update missing, opw ticket: 612847

Issue: the status tracking message is not translated into user's language
Steps to reproduce:
- install sale application, load French language, set French language to the user preference
- create a new sales quotation, tracking update into chatter shows message into French language
- confirm the quotation by clicking "Confirm Sale" button
- now, the trackng message is not in French, but it's in English

Problem: wrong context was passed into the function call

Solution: passed the updated context which contains the user's language, because write() of mail.thread does not get the context(None) when it's been called from a workflow process and we need to pass updated context.