Remove mojo::String.

device/geolocation/geolocation_service_impl.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/geolocation/geolocation_service_impl.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 60 matching lines @@
   binding_.set_connection_error_handler(base::Bind(
       &GeolocationServiceImpl::OnConnectionError, base::Unretained(this)));
 }
 
 GeolocationServiceImpl::~GeolocationServiceImpl() {
   // Make sure to respond to any pending callback even without a valid position.
   if (!position_callback_.is_null()) {
     if (!current_position_.valid) {
       current_position_.error_code = mojom::Geoposition::ErrorCode(
           GEOPOSITION_ERROR_CODE_POSITION_UNAVAILABLE);
-      current_position_.error_message = mojo::String("");
+      current_position_.error_message.clear();
     }
     ReportCurrentPosition();
   }
 }
 
 void GeolocationServiceImpl::PauseUpdates() {
   geolocation_subscription_.reset();
 }
 
 void GeolocationServiceImpl::ResumeUpdates() {
@@ skipping 89 matching lines @@
     ReportCurrentPosition();
 }
 
 void GeolocationServiceImpl::ReportCurrentPosition() {
   position_callback_.Run(current_position_.Clone());
   position_callback_.Reset();
   has_position_to_report_ = false;
 }
 
 }  // namespace device