Reduce/remove usage of BrowserThread in content/browser/loader.

content/browser/loader/resource_message_filter.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_LOADER_RESOURCE_MESSAGE_FILTER_H_
 #define CONTENT_BROWSER_LOADER_RESOURCE_MESSAGE_FILTER_H_
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "content/common/content_export.h"
 #include "content/common/url_loader_factory.mojom.h"
 #include "content/public/browser/browser_associated_interface.h"
 #include "content/public/browser/browser_message_filter.h"
-#include "content/public/browser/browser_thread.h"
 #include "content/public/common/resource_type.h"
 
 namespace storage {
 class FileSystemContext;
 }  // namespace storage
 
 namespace net {
 class URLRequestContext;
 }  // namespace net
 
@@ skipping 52 matching lines @@
   ResourceRequesterInfo* requester_info_for_test() {
     return requester_info_.get();
   }
   void InitializeForTest();
 
  protected:
   // Protected destructor so that we can be overriden in tests.
   ~ResourceMessageFilter() override;
 
  private:
-  friend struct BrowserThread::DeleteOnThread<BrowserThread::IO>;
   friend class base::DeleteHelper<ResourceMessageFilter>;
 
   // Initializes the weak pointer of this filter in |requester_info_|.
   void InitializeOnIOThread();
 
   bool is_channel_closed_;
   scoped_refptr<ResourceRequesterInfo> requester_info_;
 
   // This must come last to make sure weak pointers are invalidated first.
   base::WeakPtrFactory<ResourceMessageFilter> weak_ptr_factory_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ResourceMessageFilter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_RESOURCE_MESSAGE_FILTER_H_