Previously, when editing a review or comments as a user without

edit rights, warning users about losing unsaved work did not get

displayed.
Now the ReviewRequestEditorView's beforeUnload event handler does

not check a user's edit rights and only checks to see if any

fields are being edited at the moment.
New unit tests testing the onBeforeUnload event handler has been

added.

Ran JS unit tests.

Check that ReviewDialogView for both edit and non-edit privileged users are

warned before unloading.