title: unresponsive GUI when clicking QTreeWidgetItem - After upgrade pyqt5 from 5.10 to 5.11
body: <p>The Gui is unresponsived when I click <code>QTreeWidgetItem</code> in <code>QTreeWidget</code> in Pyqt5 5.11.3.
  The code worked in Pyqt5 5.10.1. </p>
  
  <pre><code>import sys
  from PyQt5.QtWidgets import QApplication, QDesktopWidget, QMainWindow, QTreeWidget, QTreeWidgetItem
  
  
  class DeviceTree(QTreeWidget):
      def __init__(self):
          super(DeviceTree, self).__init__()
          self.root = QTreeWidgetItem(self)
          self.root.setText(0, "sssss")
          self.root.setCheckState(0, 1)
  
  
  class MainUi(QMainWindow):
      def __init__(self):
          super(MainUi, self).__init__()
          self.width = 1000
          self.height = 600
          screen_geometry = QDesktopWidget().screenGeometry()
          self.setGeometry((screen_geometry.width() - self.width) / 2,(screen_geometry.height() - self.height) / 2,
                           self.width, self.height)
          self.setCentralWidget(DeviceTree())
  
  
  if __name__ == '__main__':
      app = QApplication(sys.argv)
      main_ui = MainUi()
      main_ui.show()
      sys.exit(app.exec_())
  </code></pre>
  
  <p>In <code>PyQt5 5.10.1</code>, the code works will. I can click the item as long as I wish.
  But in <code>PyQt5 5.11.3</code>, after click one or more times, the GUI is unresponsive.
  How to make it works in <code>PyQt5 5.11.3</code>?</p>