Add regex escaping code to Mac sandbox implementation and re-enable the utility process on OS X.

chrome/browser/extensions/extension_updater.cc

 // Copyright (c) 2009 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/extension_updater.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/logging.h"
@@ skipping 251 matching lines @@
 
   // Creates the sandboxed utility process and tells it to start parsing.
   void ParseInSandbox(ResourceDispatcherHost* rdh) {
     DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
 
     // TODO(asargent) we shouldn't need to do this branch here - instead
     // UtilityProcessHost should handle it for us. (http://crbug.com/19192)
     bool use_utility_process = rdh &&
         !CommandLine::ForCurrentProcess()->HasSwitch(switches::kSingleProcess);
 
-#if defined(OS_POSIX)
-    // TODO(port): Don't use a utility process on linux (crbug.com/22703) or
-    // MacOS (crbug.com/8102) until problems related to autoupdate are fixed.
+#if defined(OS_LINUX)
+    // TODO(port): Don't use a utility process on linux (crbug.com/22703).
     use_utility_process = false;
 #endif
 
     if (use_utility_process) {
       UtilityProcessHost* host = new UtilityProcessHost(
           rdh, this, ChromeThread::UI);
       host->StartUpdateManifestParse(xml_);
     } else {
       UpdateManifest manifest;
       if (manifest.Parse(xml_)) {
@@ skipping 427 matching lines @@
     extension_fetcher_.reset(
         URLFetcher::Create(kExtensionFetcherId, url, URLFetcher::GET, this));
     extension_fetcher_->set_request_context(
         Profile::GetDefaultRequestContext());
     extension_fetcher_->set_load_flags(net::LOAD_DO_NOT_SEND_COOKIES |
                                        net::LOAD_DO_NOT_SAVE_COOKIES);
     extension_fetcher_->Start();
     current_extension_fetch_ = ExtensionFetch(id, url, hash, version);
   }
 }