It's deciding not to emit them because the annotation stream should contain them. I'll add logic to emit the annotations if tee is true.

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/d2d28c63688f5697c611914c872da8971bde0cf5

commit d2d28c63688f5697c611914c872da8971bde0cf5
Author: dnj <dnj@chromium.org>
Date: Sat Jul 23 02:17:33 2016

Kitchen: always emit annotations if teeing.

Kitchen will not emit annotations if LogDog is enabled. However, if
Kitchen is teeing, there may be additional consumers (e.g., Milo)
reading the tee'd annotation stream. This makes it so that those
annotations will continue to be emitted if teeing.

BUG= chromium:630811 
TEST=None

Review-Url: https://codereview.chromium.org/2174103002

[modify] https://crrev.com/d2d28c63688f5697c611914c872da8971bde0cf5/go/src/infra/tools/kitchen/cook.go
[modify] https://crrev.com/d2d28c63688f5697c611914c872da8971bde0cf5/go/src/infra/tools/kitchen/cook_logdog.go

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/adefb3db3f663b1e64642461206981dc04c3f050

commit adefb3db3f663b1e64642461206981dc04c3f050
Author: nodir <nodir@chromium.org>
Date: Sat Jul 23 05:04:33 2016

kitchen: fix emission of annotations

TBR=dnj@chromium.org
BUG= 630811 

Review-Url: https://codereview.chromium.org/2173313002

[modify] https://crrev.com/adefb3db3f663b1e64642461206981dc04c3f050/go/src/infra/tools/kitchen/cook.go