CUPS: Add a regression test for duplex detection.

chrome/chrome_tests.gypi

 # Copyright (c) 2011 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.
 {
   'variables' : {
     # Variables for js2gtest rules
     'gypv8sh': '../tools/gypv8sh.py',
     'js2gtest': 'test/base/js2gtest.js',
     'mock_js': 'third_party/mock4js/mock4js.js',
     'test_api_js': 'test/data/webui/test_api.js',
@@ skipping 2334 matching lines @@
             ['exclude', '^browser/extensions/key_identifier_conversion_views_unittest.cc'],
           ],
         }],
         ['use_openssl==1', {
           'sources/': [
             # OpenSSL build does not support firefox importer. See
             # http://crbug.com/64926
             ['exclude', '^browser/importer/'],
           ],
         }],
-        ['use_cups==1 and OS!="mac"', {
+        ['use_cups==1', {
           'defines': [
             'USE_CUPS',
           ],
           'sources': [
             'browser/printing/print_system_task_proxy_unittest.cc',
           ],
         }],
       ],
     },
     {
@@ skipping 1910 matching lines @@
               # Use outputs of this action as inputs for the main target build.
               # Seems as a misnomer but makes this happy on Linux (scons).
               'process_outputs_as_sources': 1,
             },
           ],  # 'actions'
         },
       ]
     }],  # 'coverage!=0'
   ],  # 'conditions'
 }