Bug 163018 An error extension will lead the report contain chart can't be opened and can not new a report.
Details: An error extension will lead the report contain chart can't open In org.eclipse.birt.report.tests.model has an error extension. When run the birt use workbenck, the report contain chart can't be opened and it can not new a report.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/ElementDefn.java
* 
	 * @param propName
	 *            The style property name to make visible.
	 */
	void addStyleProperty( String propName )
	{
		assert !isBuilt;
		if ( stylePropertyNames == null )
			stylePropertyNames = new ArrayList( );
		stylePropertyNames.add( propName );
	}
	/**
	 * Gets the name space that holds this type of element.
	 * 
	 * @return The name space ID.
	 */
	public int getNameSpaceID( )
	{
		return nameSpaceID;
	}
	/**
	 * Gets the name option that says how the element type handles names. One of
	 * the following defined in {@link MetaDataConstants}:
	 * <ul>
	 * <li>{@link MetaDataConstants#NO_NAME}-- The element cannot have a name.
	 * (Probably not used.)</li>
	 * <li>{@link MetaDataConstants#OPTIONAL_NAME}-- The element can
	 * optionally have a name, but a name is not required.</li>
	 * <li>{@link MetaDataConstants#REQUIRED_NAME}-- The element must have a
	 * name.</li>