Bug 246105 [Dialogs] Title and description not layed out properly when title image is null
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/TitleAreaDialog.java
messageLabel.setFont(JFaceResources.getDialogFont());
		messageLabelHeight = messageLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT).y;
		
		leftFillerLabel = new Label(parent, SWT.CENTER);
		leftFillerLabel.setBackground(background);
		bottomFillerLabel = new Label(parent, SWT.CENTER);
		bottomFillerLabel.setBackground(background);
		setLayoutsForNormalMessage(verticalSpacing, horizontalSpacing);
		determineTitleImageLargest();
		if (titleImageLargest)
			return titleImageLabel;
		return messageLabel;
	}
	/**
	 * Determine if the title image is larger than the title message and message
	 * area. This is used for layout decisions.
	 */
	private void determineTitleImageLargest() {
		int titleY = titleImageLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT).y;
		int verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
		int labelY = titleLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT).y;
		labelY += verticalSpacing;
		labelY += messageLabelHeight;
		labelY += verticalSpacing;
		titleImageLargest = titleY > labelY;
	}
	/**
	 * Set the layout values for the messageLabel, messageImageLabel and
	 * fillerLabel for the case where there is a normal message.
	 *