content: Cleanup class/struct forward declarations

content/child/fileapi/webfilewriter_base.h

 // Copyright 2013 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_CHILD_FILEAPI_WEBFILEWRITER_BASE_H_
 #define CONTENT_CHILD_FILEAPI_WEBFILEWRITER_BASE_H_
 
 #include <stdint.h>
 
 #include "base/files/file.h"
 #include "content/common/content_export.h"
 #include "third_party/WebKit/public/platform/WebFileWriter.h"
 #include "url/gurl.h"
 
 namespace blink {
 class WebFileWriterClient;
-class WebURL;
 }
 
 namespace content {
 
 class CONTENT_EXPORT WebFileWriterBase
     : public NON_EXPORTED_BASE(blink::WebFileWriter) {
  public:
   WebFileWriterBase(const GURL& path, blink::WebFileWriterClient* client);
   ~WebFileWriterBase() override;
 
@@ skipping 36 matching lines @@
 
   GURL path_;
   blink::WebFileWriterClient* client_;
   OperationType operation_;
   CancelState cancel_state_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_CHILD_FILEAPI_WEBFILEWRITER_BASE_H_