celery: fix send_email to work with JSON encoding (Issue #363) Long time ago, c935bcaf7086 introduced an optional User object parameter to the send_email task and used the computed full_name_or_username property. Due to the magic of pickle, that also worked when using Celery to run the task async. Now, Celery 4 changed the default encoding from Pickle to JSON, which we anticipated in e539db6cc0da. That broke send_email in some cases, for example when a user comments on another user's changeset. Fixed by passing the "From" name as string instead of passing the whole User object. Thanks to vyom for reporting.

pytest >= 4.6.6, < 5.4
pytest-sugar >= 0.9.2, < 0.10
pytest-benchmark >= 3.2.2, < 3.3
pytest-localserver >= 0.5.0, < 0.6
mock >= 3.0.0, < 4.1
Sphinx >= 1.8.0, < 2.4
WebTest >= 2.0.6, < 2.1
isort == 4.3.21
pyflakes == 2.1.1