Turned job_factory into a pure virtual class

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 758 matching lines @@
         'url_request/url_request_filter.cc',
         'url_request/url_request_filter.h',
         'url_request/url_request_ftp_job.cc',
         'url_request/url_request_ftp_job.h',
         'url_request/url_request_http_job.cc',
         'url_request/url_request_http_job.h',
         'url_request/url_request_job.cc',
         'url_request/url_request_job.h',
         'url_request/url_request_job_factory.cc',
         'url_request/url_request_job_factory.h',
+        'url_request/url_request_job_factory_impl.cc',
+        'url_request/url_request_job_factory_impl.h',
         'url_request/url_request_job_manager.cc',
         'url_request/url_request_job_manager.h',
         'url_request/url_request_netlog_params.cc',
         'url_request/url_request_netlog_params.h',
         'url_request/url_request_redirect_job.cc',
         'url_request/url_request_redirect_job.h',
         'url_request/url_request_simple_job.cc',
         'url_request/url_request_simple_job.h',
         'url_request/url_request_status.h',
         'url_request/url_request_test_job.cc',
@@ skipping 1304 matching lines @@
                 '--result', '<@(_outputs)',
                 '--isolate', 'net_unittests.isolate',
               ],
             },
           ],
         },
       ],
     }],
   ],
 }