content: Cleanup class/struct forward declarations

content/browser/android/interstitial_page_delegate_android.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_ANDROID_INTERSTITIAL_PAGE_DELEGATE_ANDROID_H_
 #define CONTENT_BROWSER_ANDROID_INTERSTITIAL_PAGE_DELEGATE_ANDROID_H_
 
 #include <jni.h>
 #include <string>
 
 #include "base/android/jni_weak_ref.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/interstitial_page_delegate.h"
 
 namespace content {
 
 class InterstitialPage;
-class WebContents;
 
 // Native counterpart that allows interstitial pages to be constructed and
 // managed from Java.
 class InterstitialPageDelegateAndroid : public InterstitialPageDelegate {
  public:
   InterstitialPageDelegateAndroid(JNIEnv* env,
                                   jobject obj,
                                   const std::string& html_content);
   ~InterstitialPageDelegateAndroid() override;
 
@@ skipping 17 matching lines @@
 
   std::string html_content_;
   InterstitialPage* page_;  // Owns this.
 
   DISALLOW_COPY_AND_ASSIGN(InterstitialPageDelegateAndroid);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_INTERSTITIAL_PAGE_DELEGATE_ANDROID_H_