An oversight when implementing MDL-64543

> Also, I've observed that the "This script has been profiled" at the footer is always being shown... irrespectively of the run being stored or not... maybe we should fix that too and only show the message when really there is a new run to look at.

The problem with the footer may also need a 3rd indeterminate language string 'this page may be profiled' because the footer may be rendered quickly and before a long running page has finished. I'm happy to sort that too