NaCl/GYP: remove references to prep_toolchain.

remoting/remoting_key_tester.gypi

 # Copyright 2015 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.
 
 {
   'includes': [
     '../build/common_untrusted.gypi',
   ],
 
   'variables': {
@@ skipping 78 matching lines @@
             'build_pnacl_newlib': 1,
             'extra_deps_pnacl_newlib': [
               '>(tc_lib_dir_pnacl_newlib)/libppapi.a',
               '>(tc_lib_dir_pnacl_newlib)/libppapi_cpp.a',
             ],
           },
           'link_flags': [
             '-lppapi_stub',
             '-lppapi_cpp',
           ],
-          'dependencies': [
-            # TODO(mseaborn): Remove need for this (https://crbug.com/456902).
-            '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
-          ],
         },  # end of target 'remoting_key_tester_pexe'
       ],
     }]
   ],
 }