Add PointerDetails to ui::MouseEvent's constructors

ui/events/event.h

Index: ui/events/event.h
diff --git a/ui/events/event.h b/ui/events/event.h
index d121f727196e2bfbad3bb6f77fa49e41aca3255b..ab2bae4b1cafbc7b500105732d30148a42c116f5 100644
--- a/ui/events/event.h
+++ b/ui/events/event.h
@@ -519,7 +519,8 @@ class EVENTS_EXPORT MouseEvent : public LocatedEvent {
              const gfx::Point& root_location,
              base::TimeTicks time_stamp,
              int flags,
-             int changed_button_flags);
+             int changed_button_flags,
+             const PointerDetails& pointer_details);

[sadrul, 2017/04/04 03:47:14]

Most (all) users of this ctor simply pass in the default
PointerDetails(POINTER_TYPE_MOUSE) or PointerDetails(POINTER_TYPE_MOUSE,
kMousePointerId). Can we use the latter as the default argument here, so that
all the callsites don't need to do this explicitly?

Is there any callsite where some other attributes are set on the PointerDetails?

 
   // Conveniences to quickly test what button is down
   bool IsOnlyLeftMouseButton() const {