Move more metrics classes to metrics namespace.

chrome/browser/metrics/metrics_services_manager.h

Index: chrome/browser/metrics/metrics_services_manager.h
diff --git a/chrome/browser/metrics/metrics_services_manager.h b/chrome/browser/metrics/metrics_services_manager.h
index 24fc1d5f433d12e56c4e41acc47923d9a00c131c..a2f38ba7c6213c70a37ab9c8036c6f0945aac0c5 100644
--- a/chrome/browser/metrics/metrics_services_manager.h
+++ b/chrome/browser/metrics/metrics_services_manager.h
@@ -10,7 +10,6 @@
 #include "base/threading/thread_checker.h"
 
 class ChromeMetricsServiceClient;
-class MetricsService;
 class PrefService;
 
 namespace base {
@@ -18,6 +17,7 @@ class FilePath;
 }
 
 namespace metrics {
+class MetricsService;
 class MetricsStateManager;
 }
 
@@ -40,7 +40,7 @@ class MetricsServicesManager {
 
   // Returns the MetricsService, creating it if it hasn't been created yet (and
   // additionally creating the ChromeMetricsServiceClient in that case).
-  MetricsService* GetMetricsService();
+  metrics::MetricsService* GetMetricsService();
 
   // Returns the GetRapporService, creating it if it hasn't been created yet.
   rappor::RapporService* GetRapporService();