Allow menus to stay open during a child view's drag and drop

ui/views/widget/widget.cc

Index: ui/views/widget/widget.cc
diff --git a/ui/views/widget/widget.cc b/ui/views/widget/widget.cc
index fdcb32af915e97a73fead05becf0ac0c83dece35..3ccb69b5570bba07e033a5a4a4cd0b93a5ea8706 100644
--- a/ui/views/widget/widget.cc
+++ b/ui/views/widget/widget.cc
@@ -794,6 +794,7 @@ void Widget::RunShellDrag(View* view,
     dragged_view_ = NULL;
     view->OnDragDone();
   }
+  OnDragComplete();
 }
 
 void Widget::SchedulePaintInRect(const gfx::Rect& rect) {
@@ -1395,6 +1396,9 @@ void Widget::DestroyRootView() {
   input_method_.reset();
 }
 
+void Widget::OnDragComplete() {
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Widget, private: