Bug 162655 [Undo] [IDE] - Undoing a delete should check for existence of resources to be restored
N20061027. - I deleted two projects (along with their content). I read the warning that undo delete cannot restore the content and said "OK." - Then I checked out those same projects from HEAD. - Then I selected "Undo Delete Resources." This overwrote my code with empty projects. I think that "Undo Delete Resources" should become invalid if the resources exist again, because you'll end up replacing content without keeping a backup.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/undo/DeleteResourcesOperation.java
private boolean deleteContent = false;
	/**
	 * Create a DeleteResourcesOperation
	 * 
	 * @param resources
	 *            the resources to be deleted
	 * @param label
	 *            the label of the operation
	 * @param deleteContent
	 *            whether or not we are deleting content for projects
	 */
	public DeleteResourcesOperation(IResource[] resources, String label,
			boolean deleteContent) {
		super(resources, label);
		this.deleteContent = deleteContent;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * Map execution to resource deletion.
	 * 
	 * @see org.eclipse.ui.ide.undo.AbstractWorkspaceOperation#doExecute(org.eclipse.core.runtime.IProgressMonitor,
	 *      org.eclipse.core.runtime.IAdaptable)
	 */
	protected void doExecute(IProgressMonitor monitor, IAdaptable uiInfo)
			throws CoreException {