Bug 33389 Read-Only files: Quick fix enabled and gets checkmark!
RC1 1. set a file to ready only. 2. Open the file an set the cursor inside 3. Open the 'Edit' menu. Note that 'Quick fix' is enabled, but 'Content assist' is not 4. Choose 'Quick fix' 5. Open the context menu: Quick fix got a checkmark!
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
return ']';
			case ']':
				return '[';
				
			case '"':
				return character;
			
			default:
				throw new IllegalArgumentException();
		}					
	}
	
	/*
	 * @see AbstractTextEditor#handlePreferenceStoreChanged(PropertyChangeEvent)
	 */
	protected void handlePreferenceStoreChanged(PropertyChangeEvent event) {
		
		try {
			
			AdaptedSourceViewer asv= (AdaptedSourceViewer) getSourceViewer();
			if (asv != null) {
					
				String p= event.getProperty();		
				
				if (CLOSE_BRACKETS.equals(p)) {
					fBracketInserter.setCloseBracketsEnabled(getPreferenceStore().getBoolean(p));
					return;	
				}
				if (CLOSE_STRINGS.equals(p)) {
					fBracketInserter.setCloseStringsEnabled(getPreferenceStore().getBoolean(p));