Add a instance groups to Connect(), and introduce an Identity struct.

mojo/mojo_shell.gyp

 # Copyright 2015 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.
 
 {
   'targets': [{
     'target_name': 'mojo_shell_lib',
     'type': 'static_library',
     'sources': [
       'services/package_manager/loader.cc',
       'services/package_manager/loader.h',
       'services/package_manager/package_manager.cc',
       'services/package_manager/package_manager.h',
       'shell/loader.h',
       'shell/connect_params.cc',
       'shell/connect_params.h',
       'shell/connect_util.cc',
       'shell/connect_util.h',
-      'shell/identity.cc',
-      'shell/identity.h',
       'shell/native_runner.h',
       'shell/native_runner_delegate.h',
       'shell/shell.cc',
       'shell/shell.h',
       'shell/switches.cc',
       'shell/switches.cc',
       'util/filename_util.cc',
       'util/filename_util.h',
     ],
     'dependencies': [
@@ skipping 101 matching lines @@
         'dependencies': [
           '<(DEPTH)/sandbox/sandbox.gyp:sandbox',
           '<(DEPTH)/sandbox/sandbox.gyp:sandbox_services',
           '<(DEPTH)/sandbox/sandbox.gyp:seccomp_bpf',
           '<(DEPTH)/sandbox/sandbox.gyp:seccomp_bpf_helpers',
         ],
       }],
     ],
   }],
 }