Fix flowViaChannel closing immediately.

[LouisCAD]

Resolves #1259

[elizarov]

We'll drop flowViaChannel from the final 1.3.0 release, so I'm not sure it is worth to fix at this point. Most likely there will be at most one more intermediate release where it is already "fixed", but not removed. What do you think?

[LouisCAD]

I think it'd be good to have a hot-fix ASAP, so people updating from 1.2.1 to it don't encounter the almost unavoidable bug. That can help teams, or people coming back from vacations, or other tasks. Then, removing in 1.3.0 makes sense, but until then, people will already be willing to update to non preview API. Also, the difference in source between flowViaChannel and channelFlow will encourage people to be more cautious about how they update (instead of being bitten by straightforward, awaitClose-less update to channelFlow, like me yesterday). It might make sense to remove the ReplaceWith too, and use ALL_CAPS somewhere for the migration guide.

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On Fri, Jun 7, 2019, 7:30 PM Roman Elizarov ***@***.***> wrote: We'll drop flowViaChannel from the final 1.3.0 release, so I'm not sure it is worth to fix at this point. Most likely there will be at most one more intermediate release where it is already "fixed", but not removed. What do you think? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#1260?email_source=notifications&email_token=ABVG6BNTEZV7GBHPEV77OQLPZKLJ5A5CNFSM4HVYS3C2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODXGPLEY#issuecomment-499971475>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABVG6BKYTWVVE4IZUEKI6D3PZKLJ5ANCNFSM4HVYS3CQ> .

[LouisCAD]

I removed the wrong ReplaceWith clause too, and updated the deprecation message to be more helpful.