"Topic can't be blank" message when "no user selected" for private mesage

[DeanMarkTaylor (Dean Taylor)]

Steps to Reproduce

1. Select New Message button from Discourse Meta - The Official Support Forum for Discourse
2. Enter topic title / subject as “Testing”
3. Enter into the body text “The quick brown fox jumps over the lazy dog”
4. Select Message button

Expected Result

A simple clear message indicating a user must be selected.

Actual Result

Note the following about the message box contents:

• “Topic can't be blank” is incorrect.
• “no_user_selected” - is not a full English sentence.

[codinghorror (Jeff Atwood)]

Sure @techapj can you add this to your list?

[techAPJ (Arpit Jalan)]

Fixed via:

https://github.com/discourse/discourse/commit/53809d526cc7e1441666b8aca79667f642a1f3df

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