Bug 144556 [Dialogs] TitleAreaDialog fails to properly recreate when an instance is reopened
When a TitleAreaDialog is created, opened, closed and opened again on the same instance the messageArea is not properly checked against disposal when it is accessed in setWarningMessage throwing an SWTException for disposed when the message area is updated the second time the dialog is opened.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/TitleAreaDialog.java
int verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
        int horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);
        setLayoutsForNormalMessage(verticalSpacing, horizontalSpacing);
      }
    
	/**
	 * Sets whether the message area should appear or dissapear
	 * 
	 * @param visible
	 * 			<code>true</code> if the message area should be 
	 * 			displayed, and <code>false</code> otherwise.
	 */
	private void setMessageAreaVisible(boolean visible) {
		messageArea.moveAbove(null);
		
		
		
		int bottom = titleArea.getBounds().y + titleArea.getBounds().height;
		
		 
		 
		
		Rectangle msgLabelBounds = messageLabel.getBounds();
		if(!messageArea.isVisible() && messageArea.getBounds().y != bottom) {
			messageArea.setBounds(
					(messageImageLabel == null) ? msgLabelBounds.x: 
						messageImageLabel.getBounds().x,
					bottom,
					(messageImageLabel == null) ? msgLabelBounds.width: 
						msgLabelBounds.width + messageImageLabel.getBounds().width,