Show more detailed error info of navigation preload in DevTools Network tab

content/browser/devtools/protocol/network_handler.cc

 // Copyright 2014 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.
 
 #include "content/browser/devtools/protocol/network_handler.h"
 
 #include <stddef.h>
 
 #include "base/barrier_closure.h"
 #include "base/command_line.h"
@@ skipping 678 matching lines @@
       Page::ResourceTypeEnum::Other, std::move(response));
 }
 
 void NetworkHandler::NavigationPreloadCompleted(
     const std::string& request_id,
     const ResourceRequestCompletionStatus& completion_status) {
   if (!enabled_)
     return;
   if (completion_status.error_code != net::OK) {
     frontend_->LoadingFailed(
-        request_id, base::TimeTicks::Now().ToInternalValue() /
-                        static_cast<double>(base::Time::kMicrosecondsPerSecond),
-        Page::ResourceTypeEnum::Other, "Navigation Preload Error",
+        request_id,
+        base::TimeTicks::Now().ToInternalValue() /
+            static_cast<double>(base::Time::kMicrosecondsPerSecond),
+        Page::ResourceTypeEnum::Other,
+        net::ErrorToString(completion_status.error_code),
         completion_status.error_code == net::Error::ERR_ABORTED);
   }
   frontend_->LoadingFinished(
       request_id, base::TimeTicks::Now().ToInternalValue() /
                       static_cast<double>(base::Time::kMicrosecondsPerSecond),
       completion_status.encoded_data_length);
 }
 
 void NetworkHandler::NavigationFailed(
     const CommonNavigationParams& common_params,
@@ skipping 41 matching lines @@
           static_cast<double>(base::Time::kMicrosecondsPerSecond),
       Page::ResourceTypeEnum::Document, error_string, cancelled);
 }
 
 std::string NetworkHandler::UserAgentOverride() const {
   return enabled_ ? user_agent_ : std::string();
 }
 
 }  // namespace protocol
 }  // namespace content