QColorDialog: Fix matching against predefined colors.

The grids are filled top to bottom, left to right, so use division to get
the column.

Task-number: QTBUG-43371
Change-Id: I02ad518512858ed71e0e3a0cae8c4e02d537a9b9
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Blacklist ioGetFromHttpBrokenServer:no-newline

Task-number: QTBUG-43388
Change-Id: Ie589d72723520152a4cdb28b2fe40e3013b0dd50
Reviewed-by: Simo Fält <simo.falt@theqtcompany.com>