gesture: Include velocity in scroll-update gestures.

ui/base/gestures/gesture_types.cc

Index: ui/base/gestures/gesture_types.cc
diff --git a/ui/base/gestures/gesture_types.cc b/ui/base/gestures/gesture_types.cc
index 55dc7a17bbafe89efff7460b39dce857674661ac..7c0c25a51b0afc129f6bdbabe7845cc1ece507b2 100644
--- a/ui/base/gestures/gesture_types.cc
+++ b/ui/base/gestures/gesture_types.cc
@@ -45,8 +45,6 @@ GestureEventDetails::GestureEventDetails(ui::EventType type,
       break;
 
     default:
-      data.generic.delta_x = delta_x;
-      data.generic.delta_y = delta_y;
       if (delta_x != 0.f || delta_y != 0.f) {
         DLOG(WARNING) << "A gesture event (" << type << ") had unknown data: ("
                       << delta_x << "," << delta_y;
@@ -55,4 +53,11 @@ GestureEventDetails::GestureEventDetails(ui::EventType type,
   }
 }
 
+void GestureEventDetails::SetScrollVelocity(float velocity_x,
+                                            float velocity_y) {
+  CHECK_EQ(ui::ET_GESTURE_SCROLL_UPDATE, type_);
+  data.scroll.velocity_x = velocity_x;
+  data.scroll.velocity_y = velocity_y;
+}
+
 }  // namespace ui