Cross button disappear from component properties window in channel manager as well as from experiment overview dialogue

Steps to reproduce:-->
1.Open a component properties window in channel manager edit mode.
2.Notice there is no cross button in top right corner.
3.Open the experiment overview dialogue on clicking on a component for a running experiment.
4.Notice there is no cross button in top right corner.

So cross button should be visible again.Some experiment tests are failing because experiment overview remains open after experiment gets saved.