Added new features tests to AppListPresenterDelegateUnittests.

ui/events/gesture_event_details.h

Index: ui/events/gesture_event_details.h
diff --git a/ui/events/gesture_event_details.h b/ui/events/gesture_event_details.h
index 2b066d56188c5a7ae999492165d8e74b81b8734f..d826d478352408fdc71d8b38cd86687f10ca2389 100644
--- a/ui/events/gesture_event_details.h
+++ b/ui/events/gesture_event_details.h
@@ -97,7 +97,7 @@ struct EVENTS_BASE_EXPORT GestureEventDetails {
   }
 
   float velocity_y() const {
-    DCHECK_EQ(ET_SCROLL_FLING_START, type_);
+    DCHECK(ET_SCROLL_FLING_START == type_ || ET_GESTURE_SCROLL_UPDATE == type_);

[sadrul, 2017/06/20 20:43:38]

Where do we set the velocity for SCROLL_UPDATE?

[newcomer, 2017/06/20 21:23:34]

It seems like it is not set:
https://cs.chromium.org/chromium/src/ui/events/gesture_event_details.cc?dr=CS...

but this code works as intended here:
https://cs.chromium.org/chromium/src/ui/app_list/views/app_list_view.cc?q=app...

So maybe it's working by accident somehow?

[sadrul, 2017/06/20 21:39:00]

I think that code wants scroll_y(), and it happens to work because data_ is a
union, and things happen to line up. You should keep the DCHECK_EQ, and update
app-list-view to use the right thing.

[newcomer, 2017/06/20 23:42:43]

Oh, interesting. Done! Thanks for your help.

     return data_.fling_velocity.y;
   }