Add Network.setSendRequestIdHeader and use it in headless

chrome/browser/devtools/devtools_network_transaction.cc

Index: chrome/browser/devtools/devtools_network_transaction.cc
diff --git a/chrome/browser/devtools/devtools_network_transaction.cc b/chrome/browser/devtools/devtools_network_transaction.cc
index f6f0410e2030e98ad45f9d484166210054c41068..2ae4c3b560840cfa7f59e26b2d313ce5fd7f3f8b 100644
--- a/chrome/browser/devtools/devtools_network_transaction.cc
+++ b/chrome/browser/devtools/devtools_network_transaction.cc
@@ -17,11 +17,15 @@
 #include "net/socket/connection_attempts.h"
 
 // Keep in sync with X_DevTools_Emulate_Network_Conditions_Client_Id defined in
-// HTTPNames.in.
+// HTTPNames.json5.
 const char
     DevToolsNetworkTransaction::kDevToolsEmulateNetworkConditionsClientId[] =
         "X-DevTools-Emulate-Network-Conditions-Client-Id";
 
+// Keep in sync with X_DevTools_Requestt_Id defined in HTTPNames.json5.

[Sami, 2017/02/27 12:39:07]

typo: request

[alex clarke (OOO till 29th), 2017/02/27 13:51:16]

Done.

+const char DevToolsNetworkTransaction::kDevToolsRequestId[] =
+    "X-DevTools-Request-Id";
+
 DevToolsNetworkTransaction::DevToolsNetworkTransaction(
     DevToolsNetworkController* controller,
     std::unique_ptr<net::HttpTransaction> network_transaction)
@@ -120,6 +124,7 @@ int DevToolsNetworkTransaction::Start(const net::HttpRequestInfo* request,
         kDevToolsEmulateNetworkConditionsClientId, &client_id);
     custom_request_->extra_headers.RemoveHeader(
         kDevToolsEmulateNetworkConditionsClientId);
+    custom_request_->extra_headers.RemoveHeader(kDevToolsRequestId);
 
     if (request_->upload_data_stream) {
       custom_upload_data_stream_.reset(