Introduce an 'ENABLE_WEBSOCKETS' define in //net.

net/net.gyp

 # Copyright 2013 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': [
       ['chromeos==1 or embedded==1 or OS=="ios"', {
@@ skipping 259 matching lines @@
         }],
         [ 'use_openssl_certs == 0', {
             'sources!': [
               'ssl/openssl_client_key_store_unittest.cc',
             ],
         }],
         [ 'enable_websockets == 1', {
             'sources': [
               '<@(net_websockets_test_sources)',
             ],
+            'defines': [
+              'ENABLE_WEBSOCKETS',
+            ],
             'dependencies': [
               'http_server',
             ],
         }],
         ['disable_file_support==1', {
           'sources!': [
             'base/directory_lister_unittest.cc',
             'base/directory_listing_unittest.cc',
             'url_request/url_request_file_dir_job_unittest.cc',
             'url_request/url_request_file_job_unittest.cc',
@@ skipping 1474 matching lines @@
             '../build/isolate.gypi',
           ],
           'sources': [
             'net_unittests.isolate',
           ],
         },
       ],
     }],
   ],
 }