Create MetricsPrivateDelegate for metricsPrivate behavior

extensions/shell/browser/shell_extensions_api_client.h

 // 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.
 
 #ifndef EXTENSIONS_SHELL_BROWSER_SHELL_EXTENSIONS_API_CLIENT_H_
 #define EXTENSIONS_SHELL_BROWSER_SHELL_EXTENSIONS_API_CLIENT_H_
 
+#include <memory>
+
 #include "extensions/browser/api/extensions_api_client.h"
 
 namespace extensions {
 
 class ShellExtensionsAPIClient : public ExtensionsAPIClient {
  public:
   ShellExtensionsAPIClient();
 
   // ExtensionsAPIClient implementation.
   void AttachWebContentsHelpers(content::WebContents* web_contents) const
       override;
   AppViewGuestDelegate* CreateAppViewGuestDelegate() const override;
+  std::unique_ptr<MetricsPrivateDelegate> CreateMetricsPrivateDelegate()
+      const override;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_SHELL_BROWSER_SHELL_EXTENSIONS_API_CLIENT_H_