net/http: 308 redirects should use the previous hop's body
On a 301 redirect, the HTTP client changes the request to be
a GET with no body.
On a 308 redirect, the client leaves the request method and
body unchanged.
A 308 following a 301 should preserve the rewritten request
from the first redirect: GET with no body. We were preserving
the method, but sending the original body. Fix this.
Fixes #70180
Change-Id: Ie20027a6058a82bfdffc7197d07ac6c7f98099e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/626055 Reviewed-by: Jonathan Amsterdam <jba@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>