This commit renames the class of both cancel button and the cross
icon to close-modal-btn.
This change is a prep commit for enabling background events on
'hidden.bs.modal' event. As we would enable background events in
furhter commit using the 'hidden.bs.modal' event, we would need to
remove the 'hide.bs.modal' event of deactivation_stream_modal which
removes the modal element from DOM.
When we remove this we would need a e.stopPropagation call to avoid
unexpected closing of subscription settings, which was not a problem
before as the element was removed from DOM before the actual closing
of modal.
So instead of adding a separate `e.stopPropagation' call, we can use
the same handler that is being used for stream privacy modal and this
is the reason the class name of cancel button of privacy modal is
being changed.
sahil839
Anders Kaseorg