Add UMA for High Resolution Timer Usage

base/timer/hi_res_timer_manager.h

Index: base/timer/hi_res_timer_manager.h
diff --git a/base/timer/hi_res_timer_manager.h b/base/timer/hi_res_timer_manager.h
index 21cdfafb6ca844687d9135dd08e03b685926bafa..bfa316d87cc97a726484ddb15697908d361e5624 100644
--- a/base/timer/hi_res_timer_manager.h
+++ b/base/timer/hi_res_timer_manager.h
@@ -7,7 +7,10 @@
 
 #include "base/base_export.h"
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "base/power_monitor/power_observer.h"
+#include "base/timer/timer.h"
+#include "build/build_config.h"
 
 namespace base {
 
@@ -18,8 +21,10 @@ class BASE_EXPORT HighResolutionTimerManager : public base::PowerObserver {
   HighResolutionTimerManager();
   ~HighResolutionTimerManager() override;
 
-  // base::PowerObserver method.
+  // base::PowerObserver methods.
   void OnPowerStateChange(bool on_battery_power) override;
+  void OnSuspend() override;
+  void OnResume() override;
 
   // Returns true if the hi resolution clock could be used right now.
   bool hi_res_clock_available() const { return hi_res_clock_available_; }
@@ -30,6 +35,11 @@ class BASE_EXPORT HighResolutionTimerManager : public base::PowerObserver {
 
   bool hi_res_clock_available_;
 
+#if defined(OS_WIN)
+  // Timer for polling the high resolution timer usage.
+  base::RepeatingTimer timer_;
+#endif
+
   DISALLOW_COPY_AND_ASSIGN(HighResolutionTimerManager);
 };