inputhookqt4: need to ignore CTRL+C when exiting input hook

IPython/lib/inputhookqt4.py

@@ -88,6 +88,7 b' def create_inputhook_qt4(mgr, app=None):'
                     timer.start(50)
                     app.exec_()
                     timer.stop()
+            ignore_CTRL_C()
         except KeyboardInterrupt:
             ignore_CTRL_C()
             got_kbdint[0] = True