combobox: Also preselect active item in grid popup

combobox: Also preselect active item in grid popup

i.e. when wrap-width > 0. This was only being done for non-grid cases.
So, ComboBoxes in grid mode did not indicate their selection when popped
up and required users to keynav from ‘nothing’ (at the top-left) to the
item they wanted to select. By selecting the active item in advance, now
it’s highlighted & acts as the starting point for keynav around the grid