Plumb firing passive event listeners.

cc/input/input_handler.h

Index: cc/input/input_handler.h
diff --git a/cc/input/input_handler.h b/cc/input/input_handler.h
index 71505d6165a379e211aea5789806f3ffee6d98e1..4722b155e5111a62ca8b6743e8b17827bca47f3b 100644
--- a/cc/input/input_handler.h
+++ b/cc/input/input_handler.h
@@ -171,12 +171,15 @@ class CC_EXPORT InputHandler {
   virtual bool IsCurrentlyScrollingLayerAt(const gfx::Point& viewport_point,
                                            ScrollInputType type) const = 0;
 
-  virtual bool HaveWheelEventHandlersAt(const gfx::Point& viewport_point) = 0;
-
   // Whether the page should be given the opportunity to suppress scrolling by
   // consuming touch events that started at |viewport_point|.
   virtual bool DoTouchEventsBlockScrollAt(const gfx::Point& viewport_point) = 0;
 
+  virtual uint32_t EffectiveWheelEventListenerPropertiesAt(

[Rick Byers, 2016/01/26 19:17:21]

nit: please add comments describing these APIs - especially the semantics of the
return value (personally I had the convention of using bare types for flags for
this reason, but a good comment is good enough).

+      const gfx::Point& viewport_point) = 0;
+  virtual uint32_t EffectiveTouchEventListenerPropertiesAt(
+      const gfx::Point& viewport_point) = 0;
+
   // Calling CreateLatencyInfoSwapPromiseMonitor() to get a scoped
   // LatencyInfoSwapPromiseMonitor. During the life time of the
   // LatencyInfoSwapPromiseMonitor, if SetNeedsRedraw() or SetNeedsRedrawRect()