Follow on for gesture events generated by wheel events.

content/browser/renderer_host/overscroll_controller.h

Index: content/browser/renderer_host/overscroll_controller.h
diff --git a/content/browser/renderer_host/overscroll_controller.h b/content/browser/renderer_host/overscroll_controller.h
index 92fa093bf13ca43776b97eb0c177686c99a70d08..90f310f19fb2edede6c0b0384d3f61ca427ee98a 100644
--- a/content/browser/renderer_host/overscroll_controller.h
+++ b/content/browser/renderer_host/overscroll_controller.h
@@ -92,9 +92,7 @@ class OverscrollController {
   // and the over scroll amount (i.e. |overscroll_mode_|, |overscroll_delta_x_|
   // and |overscroll_delta_y_|). Returns true if overscroll was handled by the
   // delegate.
-  bool ProcessOverscroll(float delta_x,
-                         float delta_y,
-                         blink::WebInputEvent::Type event_type);
+  bool ProcessOverscroll(float delta_x, float delta_y, bool is_touchpad);
 
   // Completes the desired action from the current gesture.
   void CompleteAction();
@@ -103,6 +101,9 @@ class OverscrollController {
   // appropriate).
   void SetOverscrollMode(OverscrollMode new_mode);
 
+  // Whether this event should be processed or not handled by the controller.
+  bool ShouldProcessEvent(const blink::WebInputEvent& event);
+
   // The current state of overscroll gesture.
   OverscrollMode overscroll_mode_;
 
@@ -121,6 +122,7 @@ class OverscrollController {
   // The delegate that receives the overscroll updates. The delegate is not
   // owned by this controller.
   OverscrollControllerDelegate* delegate_;
+  bool use_gesture_wheel_scrolling_;
 
   DISALLOW_COPY_AND_ASSIGN(OverscrollController);
 };