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
* 
	 * Where are the images? The images (typically gifs) are found in the same
	 * location as this plug-in class. This may mean the same package directory
	 * as the package holding this class. The images are declared using
	 * this.getClass() to ensure they are looked up via this plug-in class.
	 * 
	 */
	public static ImageRegistry initializeImageRegistry( )
	{
		imageRegistry = ReportPlugin.getDefault( ).getImageRegistry( );
		declareImages( );
		return imageRegistry;
	}
	/**
	 * Gets the proper symbol name for the specified icon of the extended
	 * element
	 * 
	 * @param extensionName
	 *            the extension name of the element
	 * @param attrbuteName
	 *            the name of the attribute which defines an icon
	 * 
	 * @return Returns the symbol name generated
	 */
	public static String getIconSymbolName( String extensionName,
			String attrbuteName )
	{
		return attrbuteName + "." + extensionName; 
	}
}