Add method to TouchSelectionController to check if a handle is currently being

ui/base/touch/touch_editing_controller.h

Index: ui/base/touch/touch_editing_controller.h
diff --git a/ui/base/touch/touch_editing_controller.h b/ui/base/touch/touch_editing_controller.h
index 69484d2d63ef65b39687a9334d9e5c146e95f2b9..72376b21a4439d915a48f5290785166825076d5d 100644
--- a/ui/base/touch/touch_editing_controller.h
+++ b/ui/base/touch/touch_editing_controller.h
@@ -67,6 +67,9 @@ class UI_EXPORT TouchSelectionController {
 
   // Notifies the controller that the selection has changed.
   virtual void SelectionChanged() = 0;
+
+  // Returns true if the user is currently dragging one of the handles.
+  virtual bool IsHandleDragInProgress() = 0;
 };
 
 class UI_EXPORT TouchSelectionControllerFactory {