Drag and drop cleans up touch sequences from the source window.

ash/drag_drop/drag_drop_controller.cc

Index: ash/drag_drop/drag_drop_controller.cc
diff --git a/ash/drag_drop/drag_drop_controller.cc b/ash/drag_drop/drag_drop_controller.cc
index e2c6e6a43ebdf1cc673b58d665136144af635e89..9b7bd19a6faf87d4cb7b21355b3d37450a6160a4 100644
--- a/ash/drag_drop/drag_drop_controller.cc
+++ b/ash/drag_drop/drag_drop_controller.cc
@@ -173,8 +173,9 @@ int DragDropController::StartDragAndDrop(
     // We need to transfer the current gesture sequence and the GR's touch event
     // queue to the |drag_drop_tracker_|'s capture window so that when it takes
     // capture, it still gets a valid gesture state.
-    ui::GestureRecognizer::Get()->TransferEventsTo(source_window,
-        tracker->capture_window());
+    ui::GestureRecognizer::Get()->TransferEventsTo(
+        source_window, tracker->capture_window(),
+        ui::GestureRecognizer::ShouldCancelTouches::Cancel);
     // We also send a gesture end to the source window so it can clear state.
     // TODO(varunjain): Remove this whole block when gesture sequence
     // transferring is properly done in the GR (http://crbug.com/160558)