Revert of Fix sticky keys crash when handling synthetic events without a native event.

ui/events/event.h

Index: ui/events/event.h
diff --git a/ui/events/event.h b/ui/events/event.h
index 17cad8b301ecd1c37f2cc04c5de8845b97743507..51d73f8adf8f8eab576c2e7ac9f4c14b3ef14eb4 100644
--- a/ui/events/event.h
+++ b/ui/events/event.h
@@ -416,9 +416,11 @@
   template <class T>
   MouseWheelEvent(const MouseWheelEvent& model,
                   T* source,
-                  T* target)
-      : MouseEvent(model, source, target, model.type(), model.flags()),
-        offset_(model.x_offset(), model.y_offset()) {
+                  T* target,
+                  EventType type,
+                  int flags)
+      : MouseEvent(model, source, target, type, flags),
+        offset_(model.x_offset(), model.y_offset()){
   }
 
   // The amount to scroll. This is in multiples of kWheelDelta.