base::mac::IsOSSierra() -> base::mac::IsOS10_12(), etc.

base/process/memory_mac.mm

 // Copyright (c) 2013 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/memory.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <errno.h>
 #include <mach/mach.h>
 #include <mach/mach_vm.h>
@@ skipping 230 matching lines @@
 
 void oom_killer_new() {
   TerminateBecauseOutOfMemory(0);
 }
 
 #if !defined(ADDRESS_SANITIZER)
 
 // === Core Foundation CFAllocators ===
 
 bool CanGetContextForCFAllocator() {
-  return !base::mac::IsOSLaterThanSierra_DontCallThis();
+  return !base::mac::IsOSLaterThan10_12_DontCallThis();
 }
 
 CFAllocatorContext* ContextForCFAllocator(CFAllocatorRef allocator) {
   ChromeCFAllocatorLions* our_allocator =
       const_cast<ChromeCFAllocatorLions*>(
           reinterpret_cast<const ChromeCFAllocatorLions*>(allocator));
   return &our_allocator->_context;
 }
 
 CFAllocatorAllocateCallBack g_old_cfallocator_system_default;
@@ skipping 280 matching lines @@
                                             @selector(allocWithZone:));
   g_old_allocWithZone = reinterpret_cast<allocWithZone_t>(
       method_getImplementation(orig_method));
   CHECK(g_old_allocWithZone)
       << "Failed to get allocWithZone allocation function.";
   method_setImplementation(orig_method,
                            reinterpret_cast<IMP>(oom_killer_allocWithZone));
 }
 
 }  // namespace base