Add Keyboard Latency UMA Metrics.

content/public/browser/render_widget_host.h

Index: content/public/browser/render_widget_host.h
diff --git a/content/public/browser/render_widget_host.h b/content/public/browser/render_widget_host.h
index f2f435042fce3725205731781410f8663a495ec1..272d859134afe05e83f8f23e14f9687a84d9a00a 100644
--- a/content/public/browser/render_widget_host.h
+++ b/content/public/browser/render_widget_host.h
@@ -25,6 +25,10 @@ class WebMouseEvent;
 class WebMouseWheelEvent;
 }
 
+namespace ui {
+class LatencyInfo;
+}
+
 namespace content {
 
 struct CursorInfo;
@@ -164,8 +168,9 @@ class CONTENT_EXPORT RenderWidgetHost : public IPC::Sender {
       const blink::WebMouseEvent& mouse_event) = 0;
   virtual void ForwardWheelEvent(
       const blink::WebMouseWheelEvent& wheel_event) = 0;
-  virtual void ForwardKeyboardEvent(
-      const NativeWebKeyboardEvent& key_event) = 0;
+  virtual void ForwardKeyboardEventWithLatencyInfo(
+      const NativeWebKeyboardEvent& key_event,
+      const ui::LatencyInfo& latency) = 0;
   virtual void ForwardGestureEvent(
       const blink::WebGestureEvent& gesture_event) = 0;