chrome: Cleanup class/struct forward declarations

chrome/browser/ui/android/usb_chooser_dialog_android.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_UI_ANDROID_USB_CHOOSER_DIALOG_ANDROID_H_
 #define CHROME_BROWSER_UI_ANDROID_USB_CHOOSER_DIALOG_ANDROID_H_
 
 #include <string>
 #include <vector>
 
 #include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/scoped_observer.h"
 #include "base/strings/string16.h"
 #include "device/usb/public/interfaces/chooser_service.mojom.h"
 #include "device/usb/usb_service.h"
 
 namespace content {
 class RenderFrameHost;
-class WebContents;
 }
 
 namespace device {
 class UsbDevice;
 class UsbDeviceFilter;
 }
 
 // Represents a way to ask the user to select a USB device from a list of
 // options.
 class UsbChooserDialogAndroid : public device::UsbService::Observer {
@@ skipping 46 matching lines @@
 
   std::vector<scoped_refptr<device::UsbDevice>> devices_;
 
   base::android::ScopedJavaGlobalRef<jobject> java_dialog_;
   base::WeakPtrFactory<UsbChooserDialogAndroid> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbChooserDialogAndroid);
 };
 
 #endif  // CHROME_BROWSER_UI_ANDROID_USB_CHOOSER_DIALOG_ANDROID_H_