tree decbf66318a18e67b4a340361cd33cac9b8908a3
parent 82760ceffaa2541f404cd14beb6cb35bf0d38c3c
author Joe Tsai <joetsai@digital-static.net> 1562779272 -0700
committer Joe Tsai <joetsai@digital-static.net> 1562788371 +0000

internal/impl: avoid preserving presence on proto3 bytes field

When setting a proto3 bytes field to an empty, non-nil bytes slice,
just store a nil slice in the underderlying storage.
This is done to avoid presenting the illusion to the user that
presence is preserved for proto3.

Updates golang/protobuf#896

Change-Id: I1b97bedd547d336863c65d9418d8f07edf69ccd6
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185577
Reviewed-by: Herbie Ong <herbie@google.com>