This makes selenium in Firefox work on the Mac.

tests/selenium/selenium.gyp

 # Copyright (c) 2009 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': {
     'chromium_code': 1,
     'selenium_args': [
       '--referencedir=<(screenshotsdir)',
       '--product_dir=<(PRODUCT_DIR)',
@@ skipping 58 matching lines @@
         'HOME',
         'DISPLAY',
         'XAUTHORITY',
       ],
       'run_as': {
         'working_directory': '<(DEPTH)',
         'action': [
           'python<(EXECUTABLE_SUFFIX)',
           'o3d/tests/selenium/main.py',
           '<@(selenium_args)',
+          '--browserpath=<(browser_path)',
           '--browser=*firefox',
           '--screenshotsdir=<(PRODUCT_DIR)/tests/selenium/screenshots_firefox',
         ],
       },
+      'conditions': [
+        ['OS=="win"',
+          {
+            'variables': {
+              'browser_path': '',
+            },
+          }
+        ],
+        ['OS=="linux"',
+          {
+            'variables': {
+              'browser_path': '',
+            },
+          },
+        ],
+        ['OS=="mac"',
+          {
+            'dependencies': [
+              'unpack_firefox',
+            ],
+            'variables': {
+              'browser_path': '<(PRODUCT_DIR)/selenium_firefox/Firefox.app/Contents/MacOS/firefox-bin',
+            },
+          },
+        ],
+      ],
     },
     {
       'target_name': 'selenium_chrome',
       'type': 'none',
       'dependencies': [
         'install_selenium_tests',
         '../tests.gyp:unit_tests',
         '../../plugin/plugin.gyp:npo3dautoplugin',
       ],
       'scons_propagate_variables': [
         'HOME',
         'DISPLAY',
         'XAUTHORITY',
       ],
       'run_as': {
         'action': [
           'python<(EXECUTABLE_SUFFIX)',
           'main.py',
           '<@(selenium_args)',
+          '--browserpath=<(browser_path)',
           '--browser=*googlechrome',
           '--screenshotsdir=<(PRODUCT_DIR)/tests/selenium/screenshots_chrome',
         ],
       },
       'conditions': [
+        ['OS=="win"',
+          {
+            'variables': {
+              'browser_path': '',
+            },
+          }
+        ],
         ['OS=="linux"',
           {
             'variables': {
-              'selenium_args': [
-                '--browserpath=/usr/bin/google-chrome',
-              ],
+              'browser_path': '/usr/bin/google-chrome',
             },
           },
         ],
         ['OS=="mac"',
           {
             'variables': {
-              'selenium_args': [
-                '--browserpath="/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"',
-              ],
+              'browser_path': 'mac_chrome.sh',
             },
           },
         ],
       ],
     },
   ],
   'conditions': [
     ['<(selenium_screenshots) == 1',
       {
         'variables': {
           'selenium_args': [
             '--screenshots',
           ],
         },
       },
     ],
     ['OS=="mac"',
       {
         'targets': [
           {
+            'target_name': 'unpack_firefox',
+            'type': 'none',
+            'actions': [
+              {
+                'action_name': 'unpack_firefox',
+                'inputs': [
+                  '<(PRODUCT_DIR)/O3D.plugin',
+                ],
+                'outputs': [
+                  '<(PRODUCT_DIR)/selenium_firefox',
+                ],
+                'action': [
+                  'python',
+                  'unpack_firefox.py',
+                  '--plugin_path=<(PRODUCT_DIR)/O3D.plugin',
+                  '--product_path=<(PRODUCT_DIR)',
+                ],
+              },
+            ],
+          },
+          {
             'target_name': 'selenium_safari',
             'type': 'none',
             'dependencies': [
               'install_selenium_tests',
               '../tests.gyp:unit_tests',
               '../../plugin/plugin.gyp:npo3dautoplugin',
             ],
             'run_as': {
               'action': [
                 'python<(EXECUTABLE_SUFFIX)',
@@ skipping 29 matching lines @@
                 '--browser=*iexplore',
                 '--screenshotsdir=<(PRODUCT_DIR)/tests/selenium/screenshots_ie',
               ],
             },
           },
         ],
       },
     ],
   ],
 }