Bug 57131 Remove references to AST#parseCompilationUnit from java.compare
JDT Core wants to remove the following methods (that have been deprecated for several builds now) for next integration build: - AST#parseCompilationUnit(ICompilationUnit,boolean,WorkingCopyOwner) (use ASTParser instead) - ICompilationUnit#reconcile(boolean, IProgressMonitor) (use reconcile(boolean, boolean, WorkingCopyOwner, IProgressMonitor) instead)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/compare/JavaAddElementFromHistory.java
parent= cu;
				}
			}
		} else {
			input= getEditionElement(selection);
			if (input != null) {
				cu= input.getCompilationUnit();
			
				if (input instanceof IParent) {
					parent= (IParent)input;
					input= null;
				} else {
					IJavaElement parentElement= input.getParent();
					if (parentElement instanceof IParent)
						parent= (IParent)parentElement;
				}
			} else {
				if (selection instanceof IStructuredSelection) {
					Object o= ((IStructuredSelection)selection).getFirstElement();
					if (o instanceof ICompilationUnit) {
						cu= (ICompilationUnit) o;
						parent= cu;
					}
				}
			}
		}
		
		if (parent == null || cu == null) {
			String invalidSelectionMessage= CompareMessages.getString("AddFromHistory.invalidSelectionMessage"); 
			MessageDialog.openInformation(shell, errorTitle, invalidSelectionMessage);