The following changes were implemented:
1 - Added Failed Message component and related components to reuse the
Message component when rendering failed messages. This allows us to
dispose of the messagefailed JS model altogether, since failed messages
are now just regular messages that were marked as failed.
2 - Added Owl reactivity to failed message actions so that browser does
not have to be reloaded each time a message is marked as reviewed or
resent.
3 - Fixed 'Retry' and 'Set as reviewed' flows for failed messages.
4 - Fixed `Failed sent messages` filter on models by overriding `get_view`
instead of `_fields_view_get`
5 - Refactored folder structure to more closely resemble the `mail`
module's folder structure.
6 - Refactored module to utilize `Command` as a means to create, write,
etc. instead of `[0, ...]`, `[4, ...]`.
7 - Fixed and added unit tests.
8 - Removed dead/unused code from `v15`.
In migration #873 the classes DiscussController and MailController which
are the result of an upstream functionality split are merge altogether
in this module override causing undesired side effects in other modules
trying to extend those (i.e.: portal)
TT41432
payen000
David