Rectangle Selection does not display Selection Dimensions Correctly

The rectangle, ellipse and polygon selection of the mask, brush and shape tools does not display the dimensions in grid units until the grid has been changed.

Steps to reproduce

1. Select the brush tool (or mask or shape)

2. Select the rectangle (or ellipse or polygon) mode

3. Make a selection

Expected: The pixel dimensions and grid dimensions of the selection are displayed.

Actual: The grid dimensions are only displayed when he grid has been changed.