Show selection length near line/column number

I've found myself wanting this feature on several occasions. Most recently it was for QTBUG-5903, to verify the length of a message in Creator's application output. I realise that you can e.g. save the text you're interested in to a file and use wc to achieve this, but it would be a great convenience feature.

As a reference, here's what Notepad++ does when the cursor is sitting in some text with nothing selected:

When I select some text in the middle of the line: