Remove BindStateHolder and have Bind() return a Callback<> object directly.

net/net.gyp

 # Copyright (c) 2011 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 54 matching lines @@
         'base/cert_database_mac.cc',
         'base/cert_database_nss.cc',
         'base/cert_database_openssl.cc',
         'base/cert_database_win.cc',
         'base/cert_status_flags.cc',
         'base/cert_status_flags.h',
         'base/cert_verifier.cc',
         'base/cert_verifier.h',
         'base/cert_verify_result.cc',
         'base/cert_verify_result.h',
+        'base/completion_callback.cc',
         'base/completion_callback.h',
         'base/connection_type_histograms.cc',
         'base/connection_type_histograms.h',
         'base/cookie_monster.cc',
         'base/cookie_monster.h',
         'base/cookie_options.h',
         'base/cookie_store.cc',
         'base/cookie_store.h',
         'base/cookie_util.cc',
         'base/cookie_util.h',
@@ skipping 1609 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',
           ],
         },
       ],
     }],
   ],
 }