Enable crash symbols unit test for Mac OSX.

tools/telemetry/telemetry/internal/backends/chrome/desktop_browser_backend.py

 # Copyright 2013 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.
 
 import datetime
 import glob
 import heapq
 import logging
 import os
 import os.path
@@ skipping 28 matching lines @@
   if os_name == 'mac':
     version_dir = os.path.join(os.path.dirname(executable),
                                '..',
                                'Versions')
     for version_num in os.listdir(version_dir):
       framework_file = os.path.join(version_dir,
                                     version_num,
                                     'Chromium Framework.framework',
                                     'Chromium Framework')
       if os.path.isfile(framework_file):
-        return framework_file
+        # Sometimes dyld returns symbols for a different file. Emulate what it
+        # does here by using the same mechanism to find the binary file.
+        import fcntl
+        F_GETPATH = 50
+        with open(framework_file, 'rb') as f:
+          return fcntl.fcntl(f.fileno(), F_GETPATH, b'\0' * 1024).rstrip(b'\0')
 
   return executable
 
 
 class DesktopBrowserBackend(chrome_browser_backend.ChromeBrowserBackend):
   """The backend for controlling a locally-executed browser instance, on Linux,
   Mac or Windows.
   """
   def __init__(self, desktop_platform_backend, browser_options, executable,
                flash_path, is_content_shell, browser_directory,
@@ skipping 501 matching lines @@
             self._tmp_profile_dir)
     else:
       # If we don't need the profile after the run then cleanup.
       if self._tmp_profile_dir and os.path.exists(self._tmp_profile_dir):
         shutil.rmtree(self._tmp_profile_dir, ignore_errors=True)
         self._tmp_profile_dir = None
 
     if self._tmp_output_file:
       self._tmp_output_file.close()
       self._tmp_output_file = None