Bug 120317 Set "dimension" property to 3D in "properties" view, error appears in layout editor.
Description: Set "dimension" property to 3D in "properties" view, error appears in layout editor. Steps to reproduce: 1. Add a 2D chart in property editor. 2. Set its dimension property to "three-dimension" in properties view. 3. Error appears in chart.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/ExtensionLoader.java
throws ExtensionException;
		/**
		 * Checks whether the required attribute is set.
		 * 
		 * @param name
		 *            the required attribute name
		 * @param value
		 *            the attribute value
		 * @throws ExtensionException
		 *             if the value is empty
		 */
		void checkRequiredAttribute( String name, String value )
				throws ExtensionException
		{
			if ( StringUtil.isBlank( value ) )
				throw new ExtensionException( new String[]{name},
						ExtensionException.DESIGN_EXCEPTION_VALUE_REQUIRED );
		}
		/**
		 * Loads one choice.
		 * 
		 * @param choiceTag
		 *            the choice tag
		 * @param choice
		 *            the extension choice set load
		 * @throws ExtensionException
		 *             if the class some attribute specifies can not be
		 *             instanced.
		 */
		void loadChoice( IConfigurationElement choiceTag,