Bug 189847 [DND] Combo/Text on Linux does not fire Drop event.
examples/org.eclipse.swt.examples/src/org/eclipse/swt/examples/dnd/DNDExample.java
dropOperation = DND.DROP_LINK;
					linkButton.setSelection(true);
				}
			}
			if (dropEnabled) {
				createDropTarget();
			}
		}
	});
	
	Button b = new Button(parent, SWT.CHECK);
	b.setText("DND.DROP_DEFAULT");
	defaultParent = new Composite(parent, SWT.NONE);
	b.addSelectionListener(new SelectionAdapter() {
		public void widgetSelected(SelectionEvent e) {
			Button b = (Button)e.widget;
			if (b.getSelection()) {
				dropOperation |= DND.DROP_DEFAULT;
				defaultParent.setVisible(true);			
			} else {
				dropOperation = dropOperation & ~DND.DROP_DEFAULT;
				defaultParent.setVisible(false);
			}
			if (dropEnabled) {
				createDropTarget();
			}
		}
	});
	
	defaultParent.setVisible(false);