debugger: allow short stack to be expanded by a context menu item or

double click on the "<...>" line

src/plugins/debugger/stackwindow.cpp

@@ -98,6 +98,7 @@ void StackWindow::contextMenuEvent(QContextMenuEvent *ev)
     act2->setCheckable(true);
     act2->setChecked(m_alwaysResizeColumnsToContents);
 
+    menu.addAction(theDebuggerAction(ExpandStack));
     menu.addAction(act0);
     menu.addSeparator();
     menu.addAction(act1);