tree 8b6cbf14d1f8eb3a5301259d5ad7a1807fb310ab
parent 8b366e880709d9be636fad37fdab80990e7effc9
author Joe Tsai <joetsai@digital-static.net> 1615923501 -0700
committer Joe Tsai <joetsai@digital-static.net> 1615925194 +0000

all: document that Unmarshal must be a mutable message

Fixes #937

Change-Id: I40b2678eba0195ed01676167f8e01e2fedea293b
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/302329
Trust: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Damien Neil <dneil@google.com>