[Navigation Experiment] Add WKBasedNavigationManagerImpl.

ios/web/test/fakes/test_navigation_manager_delegate.h

Index: ios/web/test/fakes/test_navigation_manager_delegate.h
diff --git a/ios/web/test/fakes/test_navigation_manager_delegate.h b/ios/web/test/fakes/test_navigation_manager_delegate.h
index 53804fb6ad58f194aa91fff3a8345e221daa5ece..3033da6e7cd05dbf9629df347a5a39e8477780ac 100644
--- a/ios/web/test/fakes/test_navigation_manager_delegate.h
+++ b/ios/web/test/fakes/test_navigation_manager_delegate.h
@@ -5,9 +5,12 @@
 #ifndef IOS_WEB_TEST_FAKES_TEST_NAVIGATION_MANAGER_DELEGATE_H_
 #define IOS_WEB_TEST_FAKES_TEST_NAVIGATION_MANAGER_DELEGATE_H_
 
+#import <WebKit/WebKit.h>
+#include <memory>
 #import "ios/web/navigation/navigation_manager_delegate.h"
 
 namespace web {
+class WebViewNavigationProxy;
 
 class TestNavigationManagerDelegate : public NavigationManagerDelegate {
  public:
@@ -19,6 +22,7 @@ class TestNavigationManagerDelegate : public NavigationManagerDelegate {
   void OnNavigationItemCommitted(
       const LoadCommittedDetails& load_details) override;
   WebState* GetWebState() override;
+  WebViewNavigationProxy* GetWebViewNavigationProxy() const override;
 };
 
 }  // namespace web