The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9

commit 4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9
Author: Vadim Tryshev <vadimt@google.com>
Date: Tue Aug 08 00:30:06 2017

Making IssuedQuery header mandatory.

Now the server sends it for 100% of requests.

Bug:  749320 
Change-Id: I0201d3e7933d32b30d926eb0f2b0fb5aa4684bfc
Reviewed-on: https://chromium-review.googlesource.com/601088
Commit-Queue: Vadim Tryshev <vadimt@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#492469}
[modify] https://crrev.com/4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9/chrome/browser/ui/app_list/search/answer_card/answer_card_search_provider.cc
[modify] https://crrev.com/4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9/chrome/browser/ui/app_list/search/answer_card/answer_card_search_provider_unittest.cc
[modify] https://crrev.com/4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9/chrome/browser/ui/app_list/search/answer_card/answer_card_web_contents.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6fdcfdde77028734f8b3bf202e5791a2bb38d6d0

commit 6fdcfdde77028734f8b3bf202e5791a2bb38d6d0
Author: Vadim Tryshev <vadimt@google.com>
Date: Tue Aug 08 17:44:21 2017

Making IssuedQuery header mandatory.

Now the server sends it for 100% of requests.

TBR=vadimt@google.com

(cherry picked from commit 4bddf9f2aa25c1686c5d9cadb6cdc0616773abb9)

Bug:  749320 
Change-Id: I0201d3e7933d32b30d926eb0f2b0fb5aa4684bfc
Reviewed-on: https://chromium-review.googlesource.com/601088
Commit-Queue: Vadim Tryshev <vadimt@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#492469}
Reviewed-on: https://chromium-review.googlesource.com/606788
Reviewed-by: Vadim Tryshev <vadimt@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#382}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/6fdcfdde77028734f8b3bf202e5791a2bb38d6d0/chrome/browser/ui/app_list/search/answer_card/answer_card_search_provider.cc
[modify] https://crrev.com/6fdcfdde77028734f8b3bf202e5791a2bb38d6d0/chrome/browser/ui/app_list/search/answer_card/answer_card_search_provider_unittest.cc
[modify] https://crrev.com/6fdcfdde77028734f8b3bf202e5791a2bb38d6d0/chrome/browser/ui/app_list/search/answer_card/answer_card_web_contents.cc