Privatize StrongBinding lifetime management

chrome/browser/media/output_protection_impl.h

 // Copyright 2016 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 CHROME_BROWSER_MEDIA_OUTPUT_PROTECTION_IMPL_H_
 #define CHROME_BROWSER_MEDIA_OUTPUT_PROTECTION_IMPL_H_
 
 #include "content/public/browser/render_frame_host.h"
 #include "media/mojo/interfaces/output_protection.mojom.h"
-#include "mojo/public/cpp/bindings/strong_binding.h"
 
 // Implements media::mojom::OutputProtection to check display links and
 // their statuses. On all platforms we'll check the network links. On ChromeOS
 // we'll also check the hardware links. Can only be used on the UI thread.
 class OutputProtectionImpl : public media::mojom::OutputProtection {
  public:
   static void Create(
       content::RenderFrameHost* render_frame_host,
       mojo::InterfaceRequest<media::mojom::OutputProtection> request);
 
-  OutputProtectionImpl(content::RenderFrameHost* render_frame_host,
-                       mojo::InterfaceRequest<OutputProtection> request);
+  explicit OutputProtectionImpl(content::RenderFrameHost* render_frame_host);
   ~OutputProtectionImpl() final;
 
   // media::mojom::OutputProtection implementation.
   void QueryStatus(const QueryStatusCallback& callback) final;
   void EnableProtection(uint32_t desired_protection_mask,
                         const EnableProtectionCallback& callback) final;
 
  private:
-  mojo::StrongBinding<media::mojom::OutputProtection> binding_;
-
   content::RenderFrameHost* const render_frame_host_;
 
   base::WeakPtrFactory<OutputProtectionImpl> weak_factory_;
 };
 
 #endif  // CHROME_BROWSER_MEDIA_OUTPUT_PROTECTION_IMPL_H_