cmd/gorebuild: check uid/gid/uname/gname/mtime fields in tgz files

Issue 61513 is resolved so this path can be turned on now.
Confirmed to still pass now that go1.21rc4 is out. It was
the first release built using improvements from CL 512437.

For golang/go#57120.
For golang/go#58884.
For golang/go#61513.

Change-Id: Ie39765f8c7ba514dea2bfccf7c8ef8acc5822a22
Reviewed-on: https://go-review.googlesource.com/c/build/+/515415
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Russ Cox <[email protected]>
Auto-Submit: Russ Cox <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Run-TryBot: Dmitri Shuralyov <[email protected]>

Author: dmitshur

cmd/gorebuild/io.go

@@ -481,13 +481,11 @@ func DiffTarGz(log *Log, rebuilt, posted []byte, fix Fixer) bool {
 		field("typeflag", r.Typeflag, p.Typeflag)
 		field("linkname", r.Linkname, p.Linkname)
 		field("mode", r.Mode, p.Mode)
-		if false { // TODO enable these after #61513 is fixed
-			field("uid", r.Uid, p.Uid)
-			field("gid", r.Gid, p.Gid)
-			field("uname", r.Uname, p.Uname)
-			field("gname", r.Gname, p.Gname)
-			field("mtime", r.ModTime, p.ModTime)
-		}
+		field("uid", r.Uid, p.Uid)
+		field("gid", r.Gid, p.Gid)
+		field("uname", r.Uname, p.Uname)
+		field("gname", r.Gname, p.Gname)
+		field("mtime", r.ModTime, p.ModTime)
 		field("atime", r.AccessTime, p.AccessTime)
 		field("ctime", r.ChangeTime, p.ChangeTime)
 		field("devmajor", r.Devmajor, p.Devmajor)