Convert some NetError[Tab]Helper messages to mojom

chrome/browser/net/net_error_tab_helper.h

Index: chrome/browser/net/net_error_tab_helper.h
diff --git a/chrome/browser/net/net_error_tab_helper.h b/chrome/browser/net/net_error_tab_helper.h
index 45b71843de333833f8e500ee3d841145206a72ef..e7b739e6cf2e335399107559aa951987b0745a0c 100644
--- a/chrome/browser/net/net_error_tab_helper.h
+++ b/chrome/browser/net/net_error_tab_helper.h
@@ -13,11 +13,17 @@
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/net/dns_probe_service.h"
 #include "chrome/common/features.h"
+#include "chrome/common/network_diagnostics.mojom.h"
 #include "components/error_page/common/net_error_info.h"
 #include "components/prefs/pref_member.h"
+#include "content/public/browser/remote_frame_interface.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
+namespace content {
+class WebContentsInterfaceRegistry;
+}
+
 namespace chrome_browser_net {
 
 // A TabHelper that monitors loads for certain types of network errors and
@@ -25,7 +31,8 @@ namespace chrome_browser_net {
 // DnsProbeService whenever a page fails to load with a DNS-related error.
 class NetErrorTabHelper
     : public content::WebContentsObserver,
-      public content::WebContentsUserData<NetErrorTabHelper> {
+      public content::WebContentsUserData<NetErrorTabHelper>,
+      public mojom::NetworkDiagnostics {
  public:
   enum TestingState {
     TESTING_DEFAULT,
@@ -75,6 +82,9 @@ class NetErrorTabHelper
   bool OnMessageReceived(const IPC::Message& message,
                          content::RenderFrameHost* render_frame_host) override;
 
+  content::WebContentsInterfaceRegistry* interfaces_for_testing() {
+    return interfaces_.get();
+  }
 
  protected:
   // |contents| is the WebContents of the tab this NetErrorTabHelper is
@@ -96,8 +106,8 @@ class NetErrorTabHelper
   void InitializePref(content::WebContents* contents);
   bool ProbesAllowed() const;
 
-  // Sanitizes |url| and shows a dialog for it.
-  void RunNetworkDiagnostics(const GURL& url);
+  // mojom::NetworkDiagnostics:
+  void RunNetworkDiagnostics(const GURL& url) override;
 
   // Shows the diagnostics dialog after its been sanitized, virtual for
   // testing.
@@ -111,6 +121,10 @@ class NetErrorTabHelper
   bool IsFromErrorPage() const;
 #endif  // BUILDFLAG(ANDROID_JAVA_UI)
 
+  std::unique_ptr<content::WebContentsInterfaceRegistry> interfaces_;
+  content::RemoteFrameInterface<mojom::NetworkDiagnosticsClient>
+      remote_network_diagnostics_client_;
+
   // True if the last provisional load that started was for an error page.
   bool is_error_page_;