Bug 87683 [Preferences] Preferences hover should show unshortened text
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/DialogMessageArea.java
newImage = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_WARNING);
            break;
        case IMessageProvider.ERROR:
            newImage = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_ERROR);
            break;
        }
        messageComposite.setVisible(true);
        titleLabel.setVisible(false);
        
        if (newMessage.equals(messageText.getText())
                && newImage == messageImageLabel.getImage())
            return;
        messageImageLabel.setImage(newImage);
        messageText.setText(Dialog.shortenText(newMessage,messageText));
        lastMessageText = newMessage;
 
    }
    /**
     * Clear the error message. Restore the previously displayed message if
     * there is one, if not restore the title label.
     *  
     */
    public void clearErrorMessage() {
        if (lastMessageText == null)
            restoreTitle();
        else
            updateText(lastMessageText, lastMessageType);
    }
}