Update a bunch of files to the new location of browser_thread.h

chrome/browser/background_mode_manager_mac.mm

 // Copyright (c) 2010 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 "base/command_line.h"
 #include "base/mac/mac_util.h"
 #include "chrome/browser/background_mode_manager.h"
-#include "chrome/browser/browser_thread.h"
 #include "chrome/common/app_mode_common_mac.h"
 #include "chrome/common/chrome_switches.h"
+#include "content/browser/browser_thread.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
 namespace {
 
 class DisableLaunchOnStartupTask : public Task {
  public:
   virtual void Run();
 };
 
@@ skipping 48 matching lines @@
                             new EnableLaunchOnStartupTask());
   } else {
     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
                             new DisableLaunchOnStartupTask());
   }
 }
 
 string16 BackgroundModeManager::GetPreferencesMenuLabel() {
   return l10n_util::GetStringUTF16(IDS_OPTIONS);
 }