Fix sends to not close the network channel.
Fix sends to not close the network channel.

Closing the channels wasn't the right thing to do. Fixing this to
unbreak workflows.

Change-Id: I4def4aab85fe94dd54d63761c3bd0a7354abecc2
Reviewed-on: https://team-review.git.corp.google.com/79716
Verified-Style: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Henning Rohde <cc74ff07599c64f633a3f6876da4eb88a647f9b9@google.com>
Verified-BuildAndTest: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

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