Chromecast buildfix: MetricsService has moved to metrics namespace.

chromecast/metrics/platform_metrics_providers.h

 // 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.
 
 #ifndef CHROMECAST_METRICS_PLATFORM_METRICS_PROVIDERS_H_
 #define CHROMECAST_METRICS_PLATFORM_METRICS_PROVIDERS_H_
 
 #include "components/metrics/proto/system_profile.pb.h"
 
+namespace metrics {
 class MetricsService;
+}
 
 namespace chromecast {
 namespace metrics {
 
 // Build-level hook for different platforms to provide data to MetricsService.
-void RegisterPlatformMetricsProviders(MetricsService* metrics_service);
+void RegisterPlatformMetricsProviders(
+    ::metrics::MetricsService* metrics_service);
 
 // Returns the current release channel.
 ::metrics::SystemProfileProto::Channel GetPlatformReleaseChannel();
 
 // Returns a string representing this build's version.
 std::string GetPlatformVersionString();
 
 // Returns whether or not metrics reporting should be on.
 bool PlatformIsReportingEnabled();
 
 // Called when the UMA client ID has been set.
 void PlatformSetClientID(const std::string& client_id);
 
 // Called when an upload has completed.
 void PlatformOnLogUploadComplete();
 
 }  // namespace metrics
 }  // namespace chromecast
 
 #endif  // CHROMECAST_METRICS_PLATFORM_METRICS_PROVIDERS_H_