Bug 122045 Template should show blank preview when there is no image
Create a template but do not associate an image with it. Place the template in the templates directory. Now, create a new report design. On the second page of the New Report dialog, select the template that has no image. Actual result: The preview appears as a white rectangle with a small red square in the top left. Expected result: The preview appears as a gray background in the preview image area.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/ReportPlatformUIImages.java
.getExtensionName( ),
					IExtensionConstants.ATTRIBUTE_KEY_OUTLINE_ICON ) );
			if ( image == null )
			{
				image = getImage( IReportGraphicConstants.ICON_ELEMENT_EXTENDED_ITEM );
			}
		}
		else if ( model instanceof DesignElementHandle )
		{
			image = getImage( ( (DesignElementHandle) model ).getElement( )
					.getDefn( ).getName( ) );
		}
		return image;
	}
	/**
	 * Gets the proper icon image descriptor for the given model
	 * 
	 * @param model
	 *            the given model
	 * @return Returns the proper icon image descriptor for the given model, or
	 *         null if no proper one exists
	 */
	public static ImageDescriptor getImageDescriptor( Object model )
	{
		ImageDescriptor imageDescriptor = null;
		if ( model instanceof ExtendedItemHandle )
		{
			imageDescriptor = getImageDescriptor( getIconSymbolName(
					( (ExtendedItemHandle) model ).getExtensionName( ),
					IExtensionConstants.ATTRIBUTE_KEY_OUTLINE_ICON ) );