Improve performance of proxy resolver by tracing DNS dependencies.

net/net_unittests.isolate

 # 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': {
     'isolate_dependency_tracked': [
       '../chrome/test/data/animate1.gif',
       '../chrome/test/data/server-unavailable.html',
       '../chrome/test/data/server-unavailable.html.mock-http-headers',
       '../chrome/test/data/simple.html',
@@ skipping 210 matching lines @@
           '../testing/test_env.py',
           '../tools/swarm_client/run_test_cases.py',
           '<(PRODUCT_DIR)/net_unittests<(EXECUTABLE_SUFFIX)',
         ],
       },
     }],
     ['OS=="mac"', {
     }, {
       'variables': {
         'isolate_dependency_tracked': [
+          'data/proxy_resolver_v8_tracing_unittest/dns_during_init.js',
+          'data/proxy_resolver_v8_tracing_unittest/dns.js',
+          'data/proxy_resolver_v8_tracing_unittest/error.js',
+          'data/proxy_resolver_v8_tracing_unittest/global_sideffects1.js',
+          'data/proxy_resolver_v8_tracing_unittest/global_sideffects2.js',
+          'data/proxy_resolver_v8_tracing_unittest/simple.js',
+          'data/proxy_resolver_v8_tracing_unittest/too_many_alerts.js',
           'data/proxy_resolver_v8_unittest/binding_from_global.js',
           'data/proxy_resolver_v8_unittest/bindings.js',
           'data/proxy_resolver_v8_unittest/direct.js',
           'data/proxy_resolver_v8_unittest/dns_fail.js',
           'data/proxy_resolver_v8_unittest/ends_with_comment.js',
           'data/proxy_resolver_v8_unittest/ends_with_statement_no_semicolon.js',
           'data/proxy_resolver_v8_unittest/international_domain_names.js',
           'data/proxy_resolver_v8_unittest/missing_close_brace.js',
           'data/proxy_resolver_v8_unittest/no_entrypoint.js',
           'data/proxy_resolver_v8_unittest/pac_library_unittest.js',
@@ skipping 261 matching lines @@
       },
     }, {
       'variables': {
         'isolate_dependency_tracked': [
           '../third_party/tlslite/tlslite/integration/TLSTwistedProtocolWrapper.py',
         ],
       },
     }],
   ],
 }