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

chrome/browser/download/download_prefs.cc

 // Copyright (c) 2011 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/download/download_prefs.h"
 
 #include "base/file_util.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
 #include "base/utf_string_conversions.h"
-#include "chrome/browser/browser_thread.h"
 #include "chrome/browser/download/download_extensions.h"
 #include "chrome/browser/download/download_util.h"
 #include "chrome/browser/download/save_package.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/common/pref_names.h"
+#include "content/browser/browser_thread.h"
 
 DownloadPrefs::DownloadPrefs(PrefService* prefs) : prefs_(prefs) {
   prompt_for_download_.Init(prefs::kPromptForDownload, prefs, NULL);
   download_path_.Init(prefs::kDownloadDefaultDirectory, prefs, NULL);
   save_file_type_.Init(prefs::kSaveFileType, prefs, NULL);
 
   // We store any file extension that should be opened automatically at
   // download completion in this pref.
   std::string extensions_to_open =
       prefs->GetString(prefs::kDownloadExtensionsToOpen);
@@ skipping 115 matching lines @@
     extensions.erase(extensions.size() - 1);
 
   prefs_->SetString(prefs::kDownloadExtensionsToOpen, extensions);
 }
 
 bool DownloadPrefs::AutoOpenCompareFunctor::operator()(
     const FilePath::StringType& a,
     const FilePath::StringType& b) const {
   return FilePath::CompareLessIgnoreCase(a, b);
 }