[7.0] Important field not escaped (Messaging / Inbox / Record Name)

1) To reproduce:
- Change the name of the demo user to <script>alert('demo user')</script>
- Go on Messaging/ Inbox menu
- If there are message that concern "demo user" then you should have a popup showing "demo user"
2) Result observed:
The script is executed
3) Result expected:
The record name should be escaped or sanitized
4) Fedora/Chrome
5) Tested on 7.0 (on runbot)