Get a minimal unit_tests target building and running for iOS

chrome/common/chrome_paths.h

 // Copyright (c) 2012 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 CHROME_COMMON_CHROME_PATHS_H__
 #define CHROME_COMMON_CHROME_PATHS_H__
 
 #include "build/build_config.h"
 
 // This file declares path keys for the chrome module.  These can be used with
@@ skipping 24 matching lines @@
                                 // "My Documents/Downloads", (Windows) or
                                 // "Downloads". (Linux)
   DIR_DEFAULT_DOWNLOADS,        // Directory for a user's downloads.
   DIR_INTERNAL_PLUGINS,         // Directory where internal plugins reside.
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   DIR_POLICY_FILES,             // Directory for system-wide read-only
                                 // policy files that allow sys-admins
                                 // to set policies for chrome. This directory
                                 // contains subdirectories.
 #endif
-#if defined(OS_MACOSX)
+#if defined(OS_MACOSX) && !defined(OS_IOS)
   DIR_MANAGED_PREFS,            // Directory that stores the managed prefs plist
                                 // files for the current user.
 #endif
-#if defined(OS_CHROMEOS) || defined(OS_MACOSX)
+#if defined(OS_CHROMEOS) || (defined(OS_MACOSX) && !defined(OS_IOS))
   DIR_USER_EXTERNAL_EXTENSIONS,  // Directory for per-user external extensions
                                  // on Chrome Mac.  On Chrome OS, this path is
                                  // used for OEM customization.
                                  // Getting this path does not create it.
 #endif
 
 #if defined(OS_LINUX)
   DIR_STANDALONE_EXTERNAL_EXTENSIONS,  // Directory for 'per-extension'
                                        // definition manifest files that
                                        // describe extensions which are to be
@@ skipping 56 matching lines @@
 
   PATH_END
 };
 
 // Call once to register the provider for the path keys defined above.
 void RegisterPathProvider();
 
 }  // namespace chrome
 
 #endif  // CHROME_COMMON_CHROME_PATHS_H__