Notify WebContentsObservers of user interactions.

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 bd6bc767fc252f6b9acf9d617dd9154aa94a1471..0b35995d752f04305b6ca3303f5df1bca876a95d 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -518,6 +518,11 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   // event and 2) enter or space key presses.
   virtual void OnUserGesture() {}
 
+  // Notification that the user has made some kind of direct input with the
+  // page. Direct input includes 1) any mouse down event; 2) any mouse wheel
+  // event; 3) any raw key down event; and 4) any gesture tap event.
+  virtual void OnUserInteraction(const blink::WebInputEvent::Type type) {}

[jdduke (slow), 2015/10/26 16:02:53]

Should we keep the naming consistent, e.g., OnUserInteractionStarted or
something like that?

[dominickn, 2015/10/27 07:03:57]

From nasko's comment, I've removed the Start prefix and replaced it with Get in
the Observer and nothing elsewhere. This is consistent with OnUserGesture

+
   // Callbacks for notification when the renderer becomes unresponsive to user
   // input events, and subsequently responsive again.
   virtual void NotifyRendererUnresponsive() {}