Bug 67168 Change Signature shows error message twice [refactoring]
200406111814 public class TestClass { void change() { } x } Try to 'Change Method Signature' on 'change()'. The error message dialog always shows up twice.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/ModifyParametersAction.java
IStructuredSelection mockSelection= new StructuredSelection(newElementToProcess);
							selectionChanged(mockSelection);
							if (isEnabled()) {
								run(mockSelection);
							} else {
								MessageDialog.openInformation(getShell(), 
									ActionMessages.getString("ModifyParameterAction.problem.title"),  
									ActionMessages.getString("ModifyParameterAction.problem.message")); 
							}
							return;
						}
					} else {
						super.activate(refactoring, parent, save);
					}
				}
				super.activate(refactoring, parent, save);
			}
		};
		starter.initialize(createWizard(changeSigRefactoring));
		try {
			starter.activate(changeSigRefactoring, getShell(), true);
		} catch (CoreException e) {
			ExceptionHandler.handle(e, 
				RefactoringMessages.getString("OpenRefactoringWizardAction.refactoring"),  
				RefactoringMessages.getString("RefactoringStarter.unexpected_exception")); 
		}
	}
}