Add Keyboard Latency UMA Metrics.

ui/latency/latency_tracker.h

Index: ui/latency/latency_tracker.h
diff --git a/ui/latency/latency_tracker.h b/ui/latency/latency_tracker.h
index 0fae6d3177024574f028e39d349eb63e4bfa5cd8..4d0a432a7c847e01b4d16cf81237f94f8877881c 100644
--- a/ui/latency/latency_tracker.h
+++ b/ui/latency/latency_tracker.h
@@ -29,7 +29,7 @@ class LatencyTracker {
       const LatencyInfo::LatencyComponent& end_component);
 
  private:
-  void ComputeTouchAndWheelScrollLatencyHistograms(
+  void ComputeEndToEndLatencyHistograms(
       const LatencyInfo::LatencyComponent& gpu_swap_begin_component,
       const LatencyInfo::LatencyComponent& gpu_swap_end_component,
       const LatencyInfo& latency);