Bug 54096 deleting elements in the outline asks for confirmation twice
i20040304 Deleting Java outline elements is behaving in a weird way in this build. I have a Java source open. I select some methods in the Outline view, and press <Del>. A dialog opens saying "Are you sure you want to delete these <#elems> elements?". I say "Yes", but the dialog opens for the second time. And while the dialog is showing up, the elements are removed from the outline. Of course, confirm the second deletion fails because the elemnts are not there anymore.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
}	
		addDragAdapters(fMethodsViewer, ops, transfers);
		
		DropTarget dropTarget = new DropTarget(fNoHierarchyShownLabel, ops | DND.DROP_DEFAULT);
		dropTarget.setTransfer(transfers);
		dropTarget.addDropListener(new TypeHierarchyTransferDropAdapter(this, fAllViewers[0]));
	}
	
	private void addDropAdapters(AbstractTreeViewer viewer, int ops, Transfer[] transfers){
		TransferDropTargetListener[] dropListeners= new TransferDropTargetListener[] {
			new TypeHierarchyTransferDropAdapter(this, viewer)
		};
		viewer.addDropSupport(ops, transfers, new DelegatingDropAdapter(dropListeners));
	}
	private void addDragAdapters(StructuredViewer viewer, int ops, Transfer[] transfers) {
		TransferDragSourceListener[] dragListeners= new TransferDragSourceListener[] {
			new SelectionTransferDragAdapter(viewer)
		};
		viewer.addDragSupport(ops, transfers, new JdtViewerDragAdapter(viewer, dragListeners));
	}	
			
	/**
	 * Returns the inner component in a workbench part.
	 * @see IWorkbenchPart#createPartControl(Composite)
	 */
	public void createPartControl(Composite container) {
						
		fPagebook= new PageBook(container, SWT.NONE);
		fWorkingSetActionGroup= new WorkingSetFilterActionGroup(JavaUI.ID_TYPE_HIERARCHY, container.getShell(), fPropertyChangeListener);