QtQuick Text property contentHeight does not behave as expected

When creating a QtQuick Text element with the property lineHeight set to a value not equal 1.0, the contentHeight is smaller than expected.

TextcontentHeightBug.png is a screen shot of the window created by the example TextcontentHeightBug.qml. The borders in the screen shot have the height bound the contentHeight of the underlying text element. On the left text item (lineHeight: 1.0) the height of the green border is as expected. The height of the red border for the text item (lineHeight: 0.5) is too small.