Notify WebContentsObservers of user interactions.

content/public/browser/web_contents_observer.h

Index: content/public/browser/web_contents_observer.h
diff --git a/content/public/browser/web_contents_observer.h b/content/public/browser/web_contents_observer.h
index c2fcffbe0f2efb50491184386b27a6aa11d21753..508c1aceefe6dad56c2b3af07acbbccf1cfcaa54 100644
--- a/content/public/browser/web_contents_observer.h
+++ b/content/public/browser/web_contents_observer.h
@@ -13,6 +13,7 @@
 #include "content/public/common/security_style.h"
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
+#include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/base/page_transition_types.h"
 #include "ui/base/window_open_disposition.h"
@@ -313,8 +314,15 @@ class CONTENT_EXPORT WebContentsObserver : public IPC::Listener,
   virtual void NavigationStopped() {}
 
   // This indicates that the next navigation was triggered by a user gesture.
+  // TODO(dominickn): remove this method in favor of DidGetUserInteraction,
+  // with the appropriate filtering by input event type.

[nasko, 2015/10/27 13:41:19]

Is this TODO expected to be resolved in this CL?

[dominickn, 2015/10/27 23:21:53]

No, I was planning on doing that in a separate CL. However, if you'd prefer it
all done in this CL then I'm happy to do it here. :)

[nasko, 2015/10/28 17:36:12]

I don't have very strong preference which way it happens. I do have a strong
desire that this happens very quickly after this one lands. 

   virtual void DidGetUserGesture() {}
 
+  // Called when there has been direct user interaction with the web contents.

[nasko, 2015/10/27 13:41:19]

nit: s/web contents/WebContents/

[dominickn, 2015/10/27 23:21:53]

Done.

+  // Direct user 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 DidGetUserInteraction(const blink::WebInputEvent::Type type) {}
+
   // This method is invoked when a RenderViewHost of this WebContents was
   // configured to ignore UI events, and an UI event took place.
   virtual void DidGetIgnoredUIEvent() {}