Currently, the option to bulk-assign Elements to within a Parent Grid's Row/RowSpan, and Col/ColSpan doesn't function, even if the Elements all share the same Definitions when selected.

Repro Steps:

1) Create a Studio Project containing a MainPage.xaml

2) Divide the RootGrid into multiple Columns.

3) Introduce multiple ContentControl Element into the Navigator, into the Root Grid.
Observe how each ContentControl has the same Col/ColSpan, and Row/RowSpan Values.

4) Use Shift+Click to select all of the introduced ContentControls.

5) Observe how the Col/ColSpan and Row/RowSpan Property fields for the ContentControls dissapear, and can not all be assigned to the same Column, and ColumnSpan of their Parent Grid all at once.

Expected Results: Multi-Editing of Row/RowSpan, and Col/ColSpan Properties are available for Elements to which share the same start values.