Add Keyboard Latency UMA Metrics.

content/browser/renderer_host/render_widget_host_impl.h

Index: content/browser/renderer_host/render_widget_host_impl.h
diff --git a/content/browser/renderer_host/render_widget_host_impl.h b/content/browser/renderer_host/render_widget_host_impl.h
index 130dc421cf923215092820aa8dd55cb3fcb26f9f..42a026cf419c4494aec100b1c92a78481b9635fe 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -151,7 +151,9 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   void SetActive(bool active) override;
   void ForwardMouseEvent(const blink::WebMouseEvent& mouse_event) override;
   void ForwardWheelEvent(const blink::WebMouseWheelEvent& wheel_event) override;
-  void ForwardKeyboardEvent(const NativeWebKeyboardEvent& key_event) override;
+  void ForwardKeyboardEventWithLatencyInfo(
+      const NativeWebKeyboardEvent& key_event,
+      const ui::LatencyInfo& ui_latency) override;
   void ForwardGestureEvent(
       const blink::WebGestureEvent& gesture_event) override;
   RenderProcessHost* GetProcess() const override;
@@ -340,6 +342,7 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   // aura.
   void ForwardKeyboardEventWithCommands(
       const NativeWebKeyboardEvent& key_event,
+      const ui::LatencyInfo& ui_latency,

[mfomitchev, 2017/04/04 14:59:06]

nit: var name is just "latency" or "latency_info" everywhere else.

[tdresser, 2017/05/01 15:49:21]

Done.

       const std::vector<EditCommand>* commands,
       bool* update_event = nullptr);