Bug 41491 Add constructors from fields issues
200300813 a. add visibility buttons like 'Add constructor from super class'
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/GenerateNewConstructorUsingFieldsAction.java
private static final int DOWN_BUTTON= IDialogConstants.CLIENT_ID + 2;
		
		private final String SETTINGS_SECTION= "GenerateConstructorUsingFieldsSelectionDialog"; 
		private final String OMIT_SUPER="OmitCallToSuper"; 
		public GenerateConstructorUsingFieldsSelectionDialog(Shell parent, ILabelProvider labelProvider, GenerateConstructorUsingFieldsContentProvider contentProvider, CompilationUnitEditor editor, IType type) {
			super(parent, labelProvider, contentProvider, editor, type);
			fContentProvider= contentProvider;
			fType= type;
			fTreeViewerAdapter= new GenerateConstructorUsingFieldsTreeViewerAdapter();
			try {
				fSuperConstructors= StubUtility.getOverridableConstructors(fType);
			} catch (CoreException e) {
				ExceptionHandler.handle(e, getShell(), fDialogTitle, ActionMessages.getString("GenerateConstructorUsingFieldsSelectionDialog.error.create.failed")); 
			}
			
			IDialogSettings dialogSettings= JavaPlugin.getDefault().getDialogSettings();
			fGenConstructorSettings= dialogSettings.getSection(SETTINGS_SECTION);
			if (fGenConstructorSettings == null) {
				fGenConstructorSettings= dialogSettings.addNewSection(SETTINGS_SECTION);
				fGenConstructorSettings.put(OMIT_SUPER, false); 
			}				
			
			fOmitSuper= fGenConstructorSettings.getBoolean(OMIT_SUPER);			
		}
		protected Control createDialogArea(Composite parent) {
			initializeDialogUnits(parent);
			Composite composite= new Composite(parent, SWT.NONE);
			GridLayout layout= new GridLayout();
			GridData gd= null;
			layout.marginHeight= convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN);