QFontMetrics returns incorrect elided text

QFontMetrics returns the wrong elided text sometimes, perhaps when the original text only has one character.

When the original text is "5" and give rect width is 5, it returns elided text "5", but it should return an empty string, because by calling `horizontalAdvance` to get the full width of text "5", it actually returns 10. 

The minimal sample code is provided below, you can see that the elided text is truncated