Make proto enums canonical for ReadState/WriteState/ConnectState.

extensions/common/api/api.gyp

 # 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: //extensions/common/api
       'target_name': 'extensions_api',
       'type': 'static_library',
       # TODO(jschuh): http://crbug.com/167187 size_t -> int
       'msvs_disabled_warnings': [ 4267 ],
       'includes': [
         '../../../build/json_schema_bundle_compile.gypi',
         '../../../build/json_schema_compile.gypi',
         'schemas.gypi',
       ],
     },
+    {
+      # Protobuf compiler / generator for chrome.cast.channel-related protocol buffers.
+      # GN version: //extensions/browser/api/cast_channel:cast_channel_proto
+      'target_name': 'cast_channel_proto',
+      'type': 'static_library',
+      'sources': [
+          'cast_channel/cast_channel.proto',
+          'cast_channel/logging.proto'
+      ],
+      'variables': {
+          'proto_in_dir': 'cast_channel',
+          'proto_out_dir': 'extensions/common/api/cast_channel',
+      },
+      'includes': [ '../../../build/protoc.gypi' ]
+    },
   ],
 }