Mojo C++ bindings: switch device/serial mojom target to use STL types.

device/serial/serial_device_enumerator_linux.cc

 // 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.
 
 #include "device/serial/serial_device_enumerator_linux.h"
 
 #include <stdint.h>
 
 #include <memory>
 #include <utility>
@@ skipping 69 matching lines @@
       uint32_t int_value;
       if (vendor_id && base::HexStringToUInt(vendor_id, &int_value)) {
         info->vendor_id = int_value;
         info->has_vendor_id = true;
       }
       if (product_id && base::HexStringToUInt(product_id, &int_value)) {
         info->product_id = int_value;
         info->has_product_id = true;
       }
       if (product_name)
-        info->display_name = product_name;
+        info->display_name.emplace(product_name);
       devices.push_back(std::move(info));
     }
   }
   return devices;
 }
 
 }  // namespace device