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

chrome/browser/extensions/extension_updater.cc

Index: chrome/browser/extensions/extension_updater.cc
diff --git a/chrome/browser/extensions/extension_updater.cc b/chrome/browser/extensions/extension_updater.cc
index a618de97bf7e43ebdfaaf4d7a02050f3eb3eff06..f79dc7d5eb39a13561e8a0a5afbbb6f0d7d29388 100644
--- a/chrome/browser/extensions/extension_updater.cc
+++ b/chrome/browser/extensions/extension_updater.cc
@@ -269,9 +269,8 @@ class SafeManifestParser : public UtilityProcessHost::Client {
     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