QDialog: allow changing no-refocus after dialog is shown

[ddenev]

Currently, we can provide a no-refocus prop to QDialog is we want to instruct the dialog to not refocus on hiding.

The current implementation though does not account for the case when we change the no-refocus prop after the dialog is shown. Setting it in this way has no effect and the dialog re-focuses anyway.

This behaviour is because in QDialog.js no-refocus is only read once in the handleShow() function.

Please add a condition to handleHide to check for the value of no-refocus once again in order to cover the case above.

My use case:
I have a dialog (A) with several buttons in it. Clicking on one of the buttons opens another dialog (B). In B there is an input field with autofocus set to true. Opening B also immediately closes A (via A.onDialogCancel()). I want to set no-refocus on A but only when I click on the button for B. Any other buttons that open dialogs - I do not want to set no-refocus for A. This is the reason why I need to be able to set no-refocus later. Also, I do not want to set no-refocus statically for A - that would mean it will always not refocus and I need this to happen only when I want it.