// Column Group Header is a part of the Group Header.
// Register the 'column group header matcher' first so that it gets
// picked up before the more general 'column header matcher'.
uiBindingRegistry.registerMouseDragMode(MouseEventMatcher
.columnGroupHeaderLeftClick(SWT.NONE), new AggregateDragMode(
new CellDragMode(), new ColumnGroupHeaderReorderDragMode(
columnGroupModel)));
uiBindingRegistry.registerMouseDragMode(
MouseEventMatcher.columnHeaderLeftClick(SWT.NONE),
new ColumnHeaderReorderDragMode(columnGroupModel));