Implement chrome://network-error with network service.

content/browser/webui/web_ui_url_loader_factory.cc

Index: content/browser/webui/web_ui_url_loader_factory.cc
diff --git a/content/browser/webui/web_ui_url_loader_factory.cc b/content/browser/webui/web_ui_url_loader_factory.cc
index fd81d67f161adb79deff6fa5fde05ca5d5712b9b..a0b651b6b99814c609ca198481d2e441c711dc7b 100644
--- a/content/browser/webui/web_ui_url_loader_factory.cc
+++ b/content/browser/webui/web_ui_url_loader_factory.cc
@@ -16,6 +16,7 @@
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/resource_context_impl.h"
+#include "content/browser/webui/network_error_url_loader.h"
 #include "content/browser/webui/url_data_manager_backend.h"
 #include "content/browser/webui/url_data_source_impl.h"
 #include "content/public/browser/browser_context.h"
@@ -247,6 +248,10 @@ class WebUIURLLoaderFactory : public mojom::URLLoaderFactory,
               base::Unretained(
                   ChromeBlobStorageContext::GetFor(browser_context_))));
       return;
+    } else if (request.url.host_piece() == kChromeUINetworkErrorHost ||
+               request.url.host_piece() == kChromeUIDinoHost) {
+      StartNetworkErrorsURLLoader(request, std::move(client));
+      return;
     }
 
     BrowserThread::PostTask(