Give access to a network time kept in the variation service.

chrome/browser/metrics/variations/variations_service.h

Index: chrome/browser/metrics/variations/variations_service.h
diff --git a/chrome/browser/metrics/variations/variations_service.h b/chrome/browser/metrics/variations/variations_service.h
index cd5bd36cd199912fb0d43d478409f9cfcbdb2cd2..6a1e17ecba2f43659b1850e8fc21fc66884725e7 100644
--- a/chrome/browser/metrics/variations/variations_service.h
+++ b/chrome/browser/metrics/variations/variations_service.h
@@ -47,6 +47,13 @@ class VariationsService
   // |CreateTrialsFromSeed|.
   void StartRepeatedVariationsSeedFetch();
 
+  // TODO(mad): Eventually move this to a NetworkTimeService.
+  // Returns a network time based on previous url request header value and CPU
+  // ticks count since then. Returns false if no network time is available yet.
+  // Can also return the error range if |uncertainty| isn't NULL.
+  bool GetNetworkTime(base::Time* network_time,
+                      base::TimeDelta* uncertainty) const;
+
 #if defined(OS_WIN)
   // Starts syncing Google Update Variation IDs with the registry.
   void StartGoogleUpdateRegistrySync();
@@ -183,6 +190,15 @@ class VariationsService
   // latency of seed requests. Initially zero.
   base::TimeTicks last_request_started_time_;
 
+  // TODO(mad): Eventually move this to a NetworkTimeService. In the mean time,
+  // these data members are used to remember and track a network time based on
+  // url request header values. |network_time_ticks_| is the ticks count when
+  // |network_time_| was set. |network_time_uncertainty_| provides an error
+  // range based on the added inaccuracies of the method used to get the time.
+  base::Time network_time_;
+  base::TimeTicks network_time_ticks_;
+  base::TimeDelta network_time_uncertainty_;
+
 #if defined(OS_WIN)
   // Helper that handles synchronizing Variations with the Registry.
   VariationsRegistrySyncer registry_syncer_;