Add CAST_PRODUCT_TYPE_AUDIO to cast metrics proto

components/metrics/proto/cast_logs.proto

 // 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.
 //
 // Cast-enabled device specific log data included in ChromeUserMetricsExtension.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package metrics;
 
 // Next tag: 4
 message CastLogsProto {
   // Cast specific device information.
   // Next tag: 4
   message CastDeviceInfo {
     // The product type of Cast device sent from Cast-enabled devices.
     // Next tag: 5
     enum CastProductType {
       CAST_PRODUCT_TYPE_UNKNOWN = 0;
       CAST_PRODUCT_TYPE_CHROMECAST = 1;
+      CAST_PRODUCT_TYPE_AUDIO = 3;
       CAST_PRODUCT_TYPE_ANDROID_TV = 4;
     }
     optional CastProductType type = 1;
 
     // The hardware revision of each product.
     optional string hardware_revision = 2;
 
     // The manufacturer of Cast device, this value is empty when the device
     // is manufactured by Google.
     optional string manufacturer = 3;
@@ skipping 98 matching lines @@
     optional fixed32 transport_connection_id = 6;
 
     // virtual_connection_id related with this event.
     optional fixed32 virtual_connection_id = 7;
 
     // An optional value for the associated event
     optional int64 value = 8;
   }
   repeated CastEventProto cast_event = 3;
 }