Bug 93245 [Dialogs] Error messages show up in two locations in the properties dialog
Force an error message: 1) select a Java project 2) open the properties dialog 3) navigate to Java Compiler>Building 4) enable project specific settings 5) enter a letter into the maximum number of problems field ->the error message shows up at the bottom 6) resize the dialog ->the error message also shows up in the banner
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferencePage.java
private Label descriptionLabel;
    /**
     * Caches size of page.
     */
    private Point size = null;
    /**
     * The message area for displaying the messages.
     * If this is <code>null</code> messages are forwarded
     * to the parent.
     */
	private MessageRegion messageArea;
    /**
     * Creates a new preference page with an empty title and no image.
     */
    protected PreferencePage() {
        this(""); 
    }
    /**
     * Creates a new preference page with the given title and no image.
     *
     * @param title the title of this preference page
     */
    protected PreferencePage(String title) {
        super(title);
    }
    /**
     * Creates a new abstract preference page with the given title and image.
     *
     * @param title the title of this preference page
     * @param image the image for this preference page,