Add GN build targets for the rest of mojo/public

mojo/mojo_public.gypi

 # Copyright 2014 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': [
     {
+      # GN version: //mojo/public/c/system
       'target_name': 'mojo_system',
       'type': 'static_library',
       'defines': [
         'MOJO_SYSTEM_IMPLEMENTATION',
       ],
       'include_dirs': [
         '..',
       ],
       'direct_dependent_settings': {
         'include_dirs': [
@@ skipping 87 matching lines @@
       'type': 'static_library',
       'include_dirs': [
         '..'
       ],
       'sources': [
         'public/js/bindings/constants.cc',
         'public/js/bindings/constants.h',
       ],
     },
     {
+      # GN version: //mojo/public/cpp/environment:standalone
       'target_name': 'mojo_environment_standalone',
       'type': 'static_library',
       'sources': [
         'public/c/environment/async_waiter.h',
         'public/c/environment/logger.h',
         'public/cpp/environment/environment.h',
         'public/cpp/environment/lib/default_async_waiter.cc',
         'public/cpp/environment/lib/default_async_waiter.h',
         'public/cpp/environment/lib/default_logger.cc',
         'public/cpp/environment/lib/default_logger.h',
         'public/cpp/environment/lib/environment.cc',
         'public/cpp/environment/lib/logging.cc',
         'public/cpp/environment/logging.h',
       ],
       'include_dirs': [
         '..',
       ],
     },
     {
+      # GN version: //mojo/public/cpp/utility
       'target_name': 'mojo_utility',
       'type': 'static_library',
       'sources': [
         'public/cpp/utility/mutex.h',
         'public/cpp/utility/run_loop.h',
         'public/cpp/utility/run_loop_handler.h',
         'public/cpp/utility/thread.h',
         'public/cpp/utility/lib/mutex.cc',
         'public/cpp/utility/lib/run_loop.cc',
         'public/cpp/utility/lib/thread.cc',
@@ skipping 25 matching lines @@
       ],
       'includes': [ 'public/tools/bindings/mojom_bindings_generator.gypi' ],
       'dependencies': [
         'mojo_cpp_bindings',
       ],
       'export_dependent_settings': [
         'mojo_cpp_bindings',
       ],
     },
     {
+      # GN version: //mojo/public/cpp/application
       'target_name': 'mojo_application',
       'type': 'static_library',
       'sources': [
         'public/cpp/application/application_impl.h',
         'public/cpp/application/connect.h',
         'public/cpp/application/lib/application_impl.cc',
         'public/cpp/application/lib/service_connector.cc',
         'public/cpp/application/lib/service_connector.h',
         'public/cpp/application/lib/application_connection.cc',
         'public/cpp/application/lib/application_delegate.cc',
@@ skipping 27 matching lines @@
           },
           'dependencies': [
             'mojo_public_java',
           ],
           'includes': [ '../build/java.gypi' ],
         },
       ],
     }],
   ],
 }