Add url_request_unittest to mac build.

net/url_request/url_request_unittest.h

 // Copyright (c) 2006-2008 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.
 
 #ifndef NET_URL_REQUEST_URL_REQUEST_UNITTEST_H_
 #define NET_URL_REQUEST_URL_REQUEST_UNITTEST_H_
 
 #include <sstream>
 #include <string>
 
@@ skipping 277 matching lines @@
         test_data_directory + L"\"";
     if (!cert_path.empty()) {
       command_line.append(L" --https=\"");
       command_line.append(cert_path);
       command_line.append(L"\"");
     }
 
     ASSERT_TRUE(
         base::LaunchApp(command_line, false, true, &process_handle_)) <<
         "Failed to launch " << command_line;
-#elif defined(OS_LINUX)
-    bool tlslite_installed = !access("/usr/bin/tls.py", X_OK);
+#elif defined(OS_POSIX)
+    bool tlslite_installed = !access("/usr/bin/tls.py", X_OK) ||
+                             !access("/usr/local/bin/tls.py", X_OK);
     ASSERT_TRUE(tlslite_installed) << "tlslite not installed?  Please run 'python setup.py install' in third_party/tlslite.";
 
     std::vector<std::string> command_line;
     command_line.push_back("python");
     command_line.push_back(WideToUTF8(testserver_path));
     command_line.push_back("--port=" + port_str);
     command_line.push_back("--data-dir=" + WideToUTF8(test_data_directory));
     if (!cert_path.empty()) 
       command_line.push_back("--https=" + WideToUTF8(cert_path));
 
@@ skipping 91 matching lines @@
                    const std::wstring& document_root,
                    const std::wstring& cert_path) : TestServer(ManualInit()) {
     Init(host_name, port, document_root, cert_path);
   }
 
   virtual std::string scheme() { return std::string("https"); }
 };
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_UNITTEST_H_