Convert all usages of mojo::ErrorHandler in //device/serial to callbacks.

device/serial/data_source_sender.cc

Index: device/serial/data_source_sender.cc
diff --git a/device/serial/data_source_sender.cc b/device/serial/data_source_sender.cc
index 97029dda656e490603edea3c7d9b73161157bf4c..5b4299239560be45c0cc927f84e48aa57f7d3c1a 100644
--- a/device/serial/data_source_sender.cc
+++ b/device/serial/data_source_sender.cc
@@ -85,8 +85,10 @@ DataSourceSender::DataSourceSender(
       shut_down_(false),
       weak_factory_(this) {
   DCHECK(!ready_callback.is_null() && !error_callback.is_null());
-  binding_.set_error_handler(this);
-  client_.set_error_handler(this);
+  binding_.set_connection_error_handler(
+      base::Bind(&DataSourceSender::OnConnectionError, base::Unretained(this)));
+  client_.set_connection_error_handler(
+      base::Bind(&DataSourceSender::OnConnectionError, base::Unretained(this)));
 }
 
 void DataSourceSender::ShutDown() {