Make URL HEAD request result in empty response body

Now URL HEAD request result in non-empty response,
so I added some changes where the request appears.

Bug: 757387
Change-Id: I67354d134faa7962af680d01fb114e0cf13523db
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1767285
Commit-Queue: Canon Mukai <canonmukai@google.com>
Reviewed-by: Matt Menke <mmenke@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Adam Rice <ricea@chromium.org>
Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690685}
15 files changed