Inline request referrer serialization for debugging

In crbug.com/1090391, we're seeing crashes due to an incorrect referrer
header, so this CL, similar to crrev.com/c/1896251 and
crrev.com/c/1954211, inlines the request referrer serialization so we
can get a better stack trace from the process that the request was in
before it was sent to the Network Service.

There is a TODO to undo this, since it is not ideal, and is just
debugging behavior.

R=dcheng@chromium.org, mmenke@chromium.org

Bug: 1090391
Change-Id: Ibd186d02cf13b6bb515867323e6107b7de6a3191
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2229205Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Dominic Farolino <dom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774973}

services/network/network_service_network_delegate.cc

@@ -7,7 +7,6 @@
 #include <string>
 
 #include "base/bind.h"
-#include "base/debug/dump_without_crashing.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "components/domain_reliability/monitor.h"
@@ -259,14 +258,6 @@ bool NetworkServiceNetworkDelegate::
 
   LOG(ERROR) << "Cancelling request to " << target_url
              << " with invalid referrer " << referrer_url;
-  // Record information to help debug issues like http://crbug.com/422871.
-  if (target_url.SchemeIsHTTPOrHTTPS()) {
-    auto referrer_policy = request.referrer_policy();
-    base::debug::Alias(&referrer_policy);
-    DEBUG_ALIAS_FOR_GURL(target_buf, target_url);
-    DEBUG_ALIAS_FOR_GURL(referrer_buf, referrer_url);
-    base::debug::DumpWithoutCrashing();
-  }
   return true;
 }
 

services/network/public/cpp/url_request_mojom_traits.cc

@@ -267,4 +267,30 @@ bool StructTraits<network::mojom::DataElementDataView, network::DataElement>::
   return true;
 }
 
+// static
+const GURL&
+StructTraits<network::mojom::URLRequestDataView, network::ResourceRequest>::
+    referrer(const network::ResourceRequest& request) {
+  // TODO(crbug.com/1090391): Move this method back inline, and move the
+  // debugging logic back to NetworkServiceNetworkDelegate when the current
+  // cause of referrer mismatches is found.
+  if (request.referrer !=
+      net::URLRequestJob::ComputeReferrerForPolicy(
+          request.referrer_policy, request.referrer, request.url)) {
+    // Record information to help debug issues like http://crbug.com/422871.
+    if (request.url.SchemeIsHTTPOrHTTPS()) {
+      auto referrer_policy = request.referrer_policy;
+      base::debug::Alias(&referrer_policy);
+      DEBUG_ALIAS_FOR_GURL(target_buf, request.url);
+      DEBUG_ALIAS_FOR_GURL(referrer_buf, request.referrer);
+      DEBUG_ALIAS_FOR_GURL(
+          initiator_buf,
+          request.request_initiator.value_or(url::Origin()).GetURL())
+      base::debug::DumpWithoutCrashing();
+    }
+  }
+
+  return request.referrer;
+}
+
 }  // namespace mojo

services/network/public/cpp/url_request_mojom_traits.h

@@ -9,6 +9,7 @@
 #include <utility>
 
 #include "base/component_export.h"
+#include "base/debug/dump_without_crashing.h"
 #include "base/memory/scoped_refptr.h"
 #include "mojo/public/cpp/base/file_mojom_traits.h"
 #include "mojo/public/cpp/base/file_path_mojom_traits.h"
@@ -109,9 +110,7 @@ struct COMPONENT_EXPORT(NETWORK_CPP_BASE)
       const network::ResourceRequest& request) {
     return request.isolated_world_origin;
   }
-  static const GURL& referrer(const network::ResourceRequest& request) {
-    return request.referrer;
-  }
+  static const GURL& referrer(const network::ResourceRequest& request);
   static net::URLRequest::ReferrerPolicy referrer_policy(
       const network::ResourceRequest& request) {
     return request.referrer_policy;