Target Mac bots at 10.7+libc++ to approximate Chrome's 10.6+libc++.

gyp/tools.gyp

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
     # GYP file to build various tools.
 #
 # To build on Linux:
 #  ./gyp_skia tools.gyp && make tools
 #
 {
@@ skipping 139 matching lines @@
         '../tools/skdiff.h',
         '../tools/skdiff_html.cpp',
         '../tools/skdiff_html.h',
         '../tools/skdiff_main.cpp',
         '../tools/skdiff_utils.cpp',
         '../tools/skdiff_utils.h',
       ],
       'dependencies': [
         'skia_lib.gyp:skia_lib',
       ],
-      'xcode_settings': {
-        'conditions': [
-          [ 'skia_osx_deployment_target==""', {
-            'MACOSX_DEPLOYMENT_TARGET': '10.7', # -mmacos-version-min, passed in env to ld.
-          }, {
-            'MACOSX_DEPLOYMENT_TARGET': '<(skia_osx_deployment_target)',
-          }],
-        ],
-        'CLANG_CXX_LIBRARY': 'libc++',
-      },
     },
     {
       'target_name': 'skpdiff',
       'type': 'executable',
       'sources': [
         '../tools/skpdiff/skpdiff_main.cpp',
         '../tools/skpdiff/SkDiffContext.cpp',
         '../tools/skpdiff/SkImageDiffer.cpp',
         '../tools/skpdiff/SkPMetric.cpp',
         '../tools/skpdiff/skpdiff_util.cpp',
@@ skipping 558 matching lines @@
               'flags.gyp:flags',
               'skia_lib.gyp:skia_lib',
               'resources',
             ],
           },
         ],
       },
     ],
   ],
 }