Enable zlib SIMD optimisations on Mac OS X builds

third_party/zlib/zlib.gyp

 # 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.
 
 {
   'targets': [
     {
       'target_name' : 'zlib_x86_simd',
       'type': 'static_library',
       'conditions': [
-        # See http://crbug.com/420616 gyp on mac & ios doesn't apply cflags
-        ['OS!="ios" and OS!="mac" and (target_arch=="ia32" or target_arch=="x64")', {
+        ['OS!="ios" and (target_arch=="ia32" or target_arch=="x64")', {
           'cflags' : ["-msse2", "-msse4.2", "-mpclmul"],
+          'xcode_settings' : {
+             'OTHER_CFLAGS' : ["-msse4.2", "-mpclmul"],
+          },
           'sources' : [ 'crc_folding.c',
                         'fill_window_sse.c']
         }, {
           'sources' : [ 'simd_stub.c' ],
         }], ['OS=="android"', {
           'toolsets': ['target', 'host'],
         }],
       ],
     },
     {
@@ skipping 34 matching lines @@
       ],
       'include_dirs': [
         '.',
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '.',
         ],
       },
       'conditions': [
-        ['OS!="ios" and OS!="mac" and (target_arch=="ia32" or target_arch=="x64")', {
+        ['OS!="ios" and (target_arch=="ia32" or target_arch=="x64")', {
           'sources' : [ 'x86.c', ],
         }],
         ['OS!="win"', {
           'product_name': 'chrome_zlib',
         }], ['OS=="android"', {
           'toolsets': ['target', 'host'],
         }],
       ],
     },
     {
@@ skipping 41 matching lines @@
           # fseeko64. We use fopen, ftell, and fseek instead on these
           # systems.
           'defines': [
             'USE_FILE32API'
           ],
         }],
       ],
     },
   ],
 }