Bug 169696 [Preferences] EncodingFieldEditor.setEnabled(false) has no effect
3.3 M4 Calling EncodingFieldEditor.setEnabled(false, parent) has no effect i.e. the control is still enabled.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/dialogs/AbstractEncodingFieldEditor.java
* Creates a composite with all the encoding controls.
     * <p>
     * Subclasses may extend.
     * </p>
     * 
	 * @param parent the parent widget
	 * @param numColumns the number of columns in the parent
	 * @return the group control
	 */
	protected Composite createEncodingGroup(Composite parent, int numColumns) {
		Font font = parent.getFont();
		Group group = new Group(parent, SWT.NONE);
		GridData data = new GridData(GridData.FILL_HORIZONTAL);
		group.setLayoutData(data);
		GridLayout layout = new GridLayout();
		layout.numColumns = 2;
		group.setLayout(layout);
		group.setText(IDEWorkbenchMessages.WorkbenchPreference_encoding);
		group.setFont(font);
		SelectionAdapter buttonListener = new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				updateEncodingState(defaultEncodingButton.getSelection());
				updateValidState();
			}
		};
		defaultEncodingButton = new Button(group, SWT.RADIO);
		defaultEnc = findDefaultEncoding();
		defaultEncodingButton.setText(defaultButtonText()); 
		data = new GridData();
		data.horizontalSpan = 2;