Bug 28698 Ctrl+O (show outline) does not work if the file being shown in the editor is read only
M4 The summary tells all. Works if the file is not read only. Is this by design?
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
private final static String PRINT_MARGIN_COLUMN= PreferenceConstants.EDITOR_PRINT_MARGIN_COLUMN;
	
	private final static String SPACES_FOR_TABS= PreferenceConstants.EDITOR_SPACES_FOR_TABS;
	
	private final static String ERROR_INDICATION= PreferenceConstants.EDITOR_PROBLEM_INDICATION;
	
	private final static String ERROR_INDICATION_COLOR= PreferenceConstants.EDITOR_PROBLEM_INDICATION_COLOR;
	
	private final static String WARNING_INDICATION= PreferenceConstants.EDITOR_WARNING_INDICATION;
	
	private final static String WARNING_INDICATION_COLOR= PreferenceConstants.EDITOR_WARNING_INDICATION_COLOR;
	
	private final static String TASK_INDICATION= PreferenceConstants.EDITOR_TASK_INDICATION;
	
	private final static String TASK_INDICATION_COLOR= PreferenceConstants.EDITOR_TASK_INDICATION_COLOR;
	
	private final static String BOOKMARK_INDICATION= PreferenceConstants.EDITOR_BOOKMARK_INDICATION;
	
	private final static String BOOKMARK_INDICATION_COLOR= PreferenceConstants.EDITOR_BOOKMARK_INDICATION_COLOR;
	
	private final static String SEARCH_RESULT_INDICATION= PreferenceConstants.EDITOR_SEARCH_RESULT_INDICATION;
	
	private final static String SEARCH_RESULT_INDICATION_COLOR= PreferenceConstants.EDITOR_SEARCH_RESULT_INDICATION_COLOR;
	
	private final static String UNKNOWN_INDICATION= PreferenceConstants.EDITOR_UNKNOWN_INDICATION;
	
	private final static String UNKNOWN_INDICATION_COLOR= PreferenceConstants.EDITOR_UNKNOWN_INDICATION_COLOR;
	
	private final static String LINKED_POSITION_COLOR= PreferenceConstants.EDITOR_LINKED_POSITION_COLOR;