Emit full header and key/value-pairs.

Bug: chromium:844008
Change-Id: Ia94b841ff97d024d6ba27b1bcc2f993f95fc11fa
Reviewed-on: https://chromium-review.googlesource.com/1092698Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@google.com>
Cr-Commit-Position: refs/heads/master@{#53613}