Speculatively reverting 166585 to see if it fixes issue 160300 - 6% startup regression on Mac 10.6

base/process_util_mac.mm

 // Copyright (c) 2012 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/process_util.h"
 
 #import <Cocoa/Cocoa.h>
 #include <crt_externs.h>
 #include <dlfcn.h>
 #include <errno.h>
@@ skipping 801 matching lines @@
 
 // === C++ operator new ===
 
 void oom_killer_new() {
   debug::BreakDebugger();
 }
 
 // === Core Foundation CFAllocators ===
 
 bool CanGetContextForCFAllocator() {
-  return !base::mac::IsOSLaterThanMountainLion_DontCallThis();
+  return !base::mac::
+      IsOSDangerouslyLaterThanMountainLionForUseByCFAllocatorReplacement();
 }
 
 CFAllocatorContext* ContextForCFAllocator(CFAllocatorRef allocator) {
   if (base::mac::IsOSSnowLeopard()) {
     ChromeCFAllocatorLeopards* our_allocator =
         const_cast<ChromeCFAllocatorLeopards*>(
             reinterpret_cast<const ChromeCFAllocatorLeopards*>(allocator));
     return &our_allocator->_context;
   } else if (base::mac::IsOSLion() || base::mac::IsOSMountainLion()) {
     ChromeCFAllocatorLions* our_allocator =
@@ skipping 421 matching lines @@
   }
 }
 
 }  // namespace
 
 void EnsureProcessTerminated(ProcessHandle process) {
   WaitForChildToDie(process, kWaitBeforeKillSeconds);
 }
 
 }  // namespace base