Cleanup: Remove unneeded browser_thread.h includes.

chrome/browser/extensions/api/system_info/system_info_api.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_api.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/strings/string_util.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/api/system_storage/storage_info_provider.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
 #include "chrome/browser/storage_monitor/removable_storage_observer.h"
 #include "chrome/browser/storage_monitor/storage_info.h"
 #include "chrome/browser/storage_monitor/storage_monitor.h"
 #include "chrome/common/extensions/api/system_display.h"
 #include "chrome/common/extensions/api/system_storage.h"
+#include "content/public/browser/browser_thread.h"
 #include "ui/gfx/display_observer.h"
 
 #if defined(USE_ASH)
 #include "ash/shell.h"
 #include "ui/gfx/screen.h"
 #endif
 
 namespace extensions {
 
 using api::system_storage::StorageUnitInfo;
@@ skipping 213 matching lines @@
 void SystemInfoAPI::OnListenerRemoved(const EventListenerInfo& details) {
   if (IsSystemStorageEvent(details.event_name)) {
     StorageMonitor::GetInstance()->EnsureInitialized(
         base::Bind(&RemoveEventListener, details.event_name));
   } else {
     RemoveEventListener(details.event_name);
   }
 }
 
 }  // namespace extensions