Add a new gyp define to be used by the swarm master.

net/net.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
 
     'linux_link_kerberos%': 0,
     'conditions': [
@@ skipping 1375 matching lines @@
           'inputs': [
             'net_unittests.isolate',
             '<@(isolate_dependency_tracked)',
           ],
           'outputs': [
             '<(PRODUCT_DIR)/net_unittests.results',
           ],
           'action': [
             'python',
             '../tools/isolate/isolate.py',
-            '--mode', '<(tests_run)',
+            '--mode', '<(test_isolation_mode)',
+            '--outdir', '<(test_isolation_outdir)',
             '--variable', 'PRODUCT_DIR', '<(PRODUCT_DIR)',
             '--variable', 'OS', '<(OS)',
             '--result', '<@(_outputs)',
             'net_unittests.isolate',
           ],
         },
       ],
     },
     {
       'target_name': 'net_perftests',
@@ skipping 449 matching lines @@
             'tools/dump_cache/url_to_filename_encoder.cc',
             'tools/dump_cache/url_to_filename_encoder.h',
             'tools/dump_cache/url_utilities.h',
             'tools/dump_cache/url_utilities.cc',
           ],
         },
       ],
     }],
   ],
 }