Chromecast buildfix: MetricsService has moved to metrics namespace.

chromecast/metrics/platform_metrics_providers_simple.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 "chromecast/metrics/platform_metrics_providers.h"
 
 namespace chromecast {
 namespace metrics {
 
-void RegisterPlatformMetricsProviders(MetricsService* metrics_service) {
+void RegisterPlatformMetricsProviders(
+    ::metrics::MetricsService* metrics_service) {
 }
 
 ::metrics::SystemProfileProto::Channel GetPlatformReleaseChannel() {
   return ::metrics::SystemProfileProto::CHANNEL_STABLE;
 }
 
 std::string GetPlatformVersionString() {
   return "";
 }
 
 bool PlatformIsReportingEnabled() {
   return false;
 }
 
 void PlatformSetClientID(const std::string& client_id) {
 }
 
 void PlatformOnLogUploadComplete() {
 }
 
 }  // namespace metrics
 }  // namespace chromecast