Add Network.setSendRequestIdHeader and use it in headless

headless/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/chrome_build.gni")
 import("//headless/headless.gni")
 import("//build/util/process_version.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 import("//tools/grit/grit_rule.gni")
@@ skipping 379 matching lines @@
 
 test("headless_browsertests") {
   sources = [
     "lib/embedder_mojo_browsertest.cc",
     "lib/headless_browser_browsertest.cc",
     "lib/headless_browser_context_browsertest.cc",
     "lib/headless_devtools_client_browsertest.cc",
     "lib/headless_web_contents_browsertest.cc",
     "public/util/dom_tree_extractor_browsertest.cc",
     "public/util/flat_dom_tree_extractor_browsertest.cc",
+    "public/util/protocol_handler_request_id_browsertest.cc",
     "test/headless_browser_test.cc",
     "test/headless_browser_test.h",
     "test/headless_test_launcher.cc",
     "test/test_protocol_handler.cc",
     "test/test_protocol_handler.h",
     "test/test_url_request_job.cc",
     "test/test_url_request_job.h",
   ]
 
   data = [
@@ skipping 61 matching lines @@
 
 executable("headless_example") {
   sources = [
     "app/headless_example.cc",
   ]
 
   deps = [
     "//headless:headless_shell_lib",
   ]
 }