Geometry of glyphs with Text.NativeRendering seems to be incorrect

The glyphs come out on screen correctly but their geometry includes a lot of padding on the lower-right side which results in that we are drawing a lot of transparent pixels.

This bounding box also cause the glyph nodes to be larger than they should be which in some cases causes overlaps with surrounding elements which in turn prevents the renderer from properly batching them, which is bad for performance.

The attached image is created by adding a bit of color to all pixels filled by the QSGTextMaskMaterial fragmentShader and clearly shows the issue.