Bug 123496 [IDE] Use operation validation API for IDE actions
We should use the Resources/Core operation validation API in the IDE actions for manipulating resources.
bundles/org.eclipse.ui.ide/extensions/org/eclipse/ui/actions/CopyFilesAndFoldersOperation.java
if (sourceStore != null) {
				if (destinationStore.equals(sourceStore)
						|| (sourceParentStore != null && destinationStore
								.equals(sourceParentStore))) {
					return NLS
							.bind(
									IDEWorkbenchMessages.CopyFilesAndFoldersOperation_importSameSourceAndDest,
									sourceStore.getName());
				}
				
				
				IFileStore destinationParent = destinationStore.getParent();
				if (sourceStore.isParentOf(destinationParent))
					return IDEWorkbenchMessages.CopyFilesAndFoldersOperation_destinationDescendentError;
			}
		}
		return null;
	}
	/**
	 * Check if the destination is valid for the given source resource.
	 * 
	 * @param destination
	 *            destination container of the operation
	 * @param source
	 *            source resource
	 * @return String error message or null if the destination is valid
	 */
	private String validateLinkedResource(IContainer destination,
			IResource source) {
		if (source.isLinked() == false) {