Added an extra sync token field for extra command buffer identification.

mojo/converters/surfaces/surfaces_type_converters.cc

Index: mojo/converters/surfaces/surfaces_type_converters.cc
diff --git a/mojo/converters/surfaces/surfaces_type_converters.cc b/mojo/converters/surfaces/surfaces_type_converters.cc
index f0a32bdb37345be225b2c6c2297231a0a3cd529c..86698e75f5a38b67fda79d5b896e1a72a7caeae7 100644
--- a/mojo/converters/surfaces/surfaces_type_converters.cc
+++ b/mojo/converters/surfaces/surfaces_type_converters.cc
@@ -537,6 +537,7 @@ SyncTokenPtr TypeConverter<SyncTokenPtr, gpu::SyncToken>::Convert(
   sync_token->verified_flush = input.verified_flush();
   sync_token->namespace_id =
       static_cast<CommandBufferNamespace>(input.namespace_id());
+  sync_token->extra_data_field = input.extra_data_field();
   sync_token->command_buffer_id = input.command_buffer_id();
   sync_token->release_count = input.release_count();
   return sync_token.Pass();
@@ -547,8 +548,8 @@ gpu::SyncToken TypeConverter<gpu::SyncToken, SyncTokenPtr>::Convert(
     const SyncTokenPtr& input) {
   const gpu::CommandBufferNamespace namespace_id =
       static_cast<gpu::CommandBufferNamespace>(input->namespace_id);
-  gpu::SyncToken sync_token(namespace_id, input->command_buffer_id,
-                            input->release_count);
+  gpu::SyncToken sync_token(namespace_id, input->extra_data_field,
+                            input->command_buffer_id, input->release_count);
   if (input->verified_flush)
     sync_token.SetVerifyFlush();