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

base/mac/mac_util.h

 // 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.
 
 #ifndef BASE_MAC_MAC_UTIL_H_
 #define BASE_MAC_MAC_UTIL_H_
 
 #include <AvailabilityMacros.h>
 #include <Carbon/Carbon.h>
 #include <string>
@@ skipping 122 matching lines @@
 BASE_EXPORT bool IsOSLion();
 BASE_EXPORT bool IsOSLionOrEarlier();
 BASE_EXPORT bool IsOSLionOrLater();
 
 // Mountain Lion is Mac OS X 10.8, Darwin 12.
 BASE_EXPORT bool IsOSMountainLion();
 BASE_EXPORT bool IsOSMountainLionOrLater();
 
 // This should be infrequently used. It only makes sense to use this to avoid
 // codepaths that are very likely to break on future (unreleased, untested,
-// unborn) OS releases, or to log when the OS is newer than any known version.
-BASE_EXPORT bool IsOSLaterThanMountainLion_DontCallThis();
+// unborn) OS releases.
+BASE_EXPORT
+    bool IsOSDangerouslyLaterThanMountainLionForUseByCFAllocatorReplacement();
 
 // When the deployment target is set, the code produced cannot run on earlier
 // OS releases. That enables some of the IsOS* family to be implemented as
 // constant-value inline functions. The MAC_OS_X_VERSION_MIN_REQUIRED macro
 // contains the value of the deployment target.
 
 #if defined(MAC_OS_X_VERSION_10_7) && \
     MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_7
 #define BASE_MAC_MAC_UTIL_H_INLINED_GE_10_7
 inline bool IsOSSnowLeopard() { return false; }
@@ skipping 10 matching lines @@
 #if defined(MAC_OS_X_VERSION_10_8) && \
     MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_8
 #define BASE_MAC_MAC_UTIL_H_INLINED_GE_10_8
 inline bool IsOSMountainLionOrLater() { return true; }
 #endif
 
 #if defined(MAC_OS_X_VERSION_10_8) && \
     MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_8
 #define BASE_MAC_MAC_UTIL_H_INLINED_GT_10_8
 inline bool IsOSMountainLion() { return false; }
-inline bool IsOSLaterThanMountainLion_DontCallThis() {
+inline bool IsOSDangerouslyLaterThanMountainLionForUseByCFAllocatorReplacement()
+{
   return true;
 }
 #endif
 
 // Retrieve the system's model identifier string from the IOKit registry:
 // for example, "MacPro4,1", "MacBookPro6,1". Returns empty string upon
 // failure.
 BASE_EXPORT std::string GetModelIdentifier();
 
 // Parse a model identifier string; for example, into ("MacBookPro", 6, 1).
 // If any error occurs, none of the input pointers are touched.
 BASE_EXPORT bool ParseModelIdentifier(const std::string& ident,
                                       std::string* type,
                                       int32* major,
                                       int32* minor);
 
 }  // namespace mac
 }  // namespace base
 
 #endif  // BASE_MAC_MAC_UTIL_H_