Remove unnecessary class forward declaration for usb/bluetooth_chooser_bubble_delegate.h

chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.h

 // Copyright 2015 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_UI_BLUETOOTH_BLUETOOTH_CHOOSER_BUBBLE_DELEGATE_H_
 #define CHROME_BROWSER_UI_BLUETOOTH_BLUETOOTH_CHOOSER_BUBBLE_DELEGATE_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
 #include "chrome/browser/ui/website_settings/chooser_bubble_delegate.h"
 #include "components/bubble/bubble_reference.h"
 
-class Browser;
 class BluetoothChooserDesktop;
 
 // BluetoothChooserBubbleDelegate is a chooser that presents a list of
 // Bluetooth device names, which come from |bluetooth_chooser_desktop_|.
 // It can be used by WebBluetooth API to get the user's permission to
 // access a Bluetooth device.
 class BluetoothChooserBubbleDelegate : public ChooserBubbleDelegate {
  public:
   explicit BluetoothChooserBubbleDelegate(content::RenderFrameHost* owner);
   ~BluetoothChooserBubbleDelegate() override;
@@ skipping 24 matching lines @@
  private:
   // Each pair is a (device name, device id).
   std::vector<std::pair<base::string16, std::string>> device_names_and_ids_;
   BluetoothChooserDesktop* bluetooth_chooser_;
   BubbleReference bubble_controller_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothChooserBubbleDelegate);
 };
 
 #endif  // CHROME_BROWSER_UI_BLUETOOTH_BLUETOOTH_CHOOSER_BUBBLE_DELEGATE_H_