Cleanup: Remove unneeded browser_thread.h includes.

chrome/browser/extensions/api/system_info/system_info_provider.cc

 // 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.
 
 #include "chrome/browser/extensions/api/system_info/system_info_provider.h"
 
+#include "base/bind.h"
+#include "content/public/browser/browser_thread.h"
+
 namespace extensions {
 
 SystemInfoProvider::SystemInfoProvider()
     : is_waiting_for_completion_(false) {
   base::SequencedWorkerPool* pool = content::BrowserThread::GetBlockingPool();
   worker_pool_ = pool->GetSequencedTaskRunnerWithShutdownBehavior(
       pool->GetSequenceToken(),
       base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
 }
 
@@ skipping 39 matching lines @@
   // Post the custom query info task to blocking pool for information querying
   // and reply with OnQueryCompleted.
   base::PostTaskAndReplyWithResult(
       worker_pool_,
       FROM_HERE,
       base::Bind(&SystemInfoProvider::QueryInfo, this),
       base::Bind(&SystemInfoProvider::OnQueryCompleted, this));
 }
 
 }  // namespace extensions