content: Cleanup class/struct forward declarations

content/browser/blob_storage/blob_dispatcher_host.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 CONTENT_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_
 #define CONTENT_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/files/file.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/shared_memory_handle.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_message_filter.h"
 #include "storage/browser/blob/blob_async_builder_host.h"
 #include "storage/browser/blob/blob_transport_result.h"
 #include "storage/common/blob_storage/blob_storage_constants.h"
 
 class GURL;
 
-namespace IPC {
-class Sender;
-}
-
 namespace storage {
 class DataElement;
-class BlobDataBuilder;
 struct BlobItemBytesRequest;
 struct BlobItemBytesResponse;
 class BlobStorageContext;
 class FileSystemContext;
 }
 
 namespace content {
 class ChromeBlobStorageContext;
 
 // This class's responsibility is to listen for and dispatch blob storage
@@ skipping 104 matching lines @@
   // The set of public blob urls coined by this consumer.
   std::set<GURL> public_blob_urls_;
 
   scoped_refptr<ChromeBlobStorageContext> blob_storage_context_;
   storage::BlobAsyncBuilderHost async_builder_;
 
   DISALLOW_COPY_AND_ASSIGN(BlobDispatcherHost);
 };
 }  // namespace content
 #endif  // CONTENT_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_