Bug 122687 Libraries dont appear to allow background colors on tables to be used
If I create a table and set the background color to blue in my library and then drag the table from the library to the report the background color does not go with it.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
* Checks the parent element.
	 * 
	 * @param parent
	 *            the parent element
	 * @throws ExtendsException
	 *             throws <code>ExtendsException</code> if the parent element
	 *             is <code>NOT_FOUND</code>,<code>WRONG_TYPE</code>,
	 *             <code>SELF_EXTEND</code>,<code>CIRCULAR</code>.
	 */
	public void checkExtends( DesignElement parent ) throws ExtendsException
	{
		String extendsName = getExtendsName( );
		IElementDefn defn = getDefn( );
		if ( parent == null )
		{
			throw new ExtendsException( this, extendsName,
					ExtendsException.DESIGN_EXCEPTION_NOT_FOUND );
		}
		else if ( parent.getDefn( ) != defn )
		{
			throw new ExtendsException( this, parent,
					ExtendsException.DESIGN_EXCEPTION_WRONG_TYPE );
		}
		else if ( parent == this )
		{
			throw new ExtendsException( this, extendsName,
					ExtendsException.DESIGN_EXCEPTION_SELF_EXTEND );
		}
		else if ( parent.isKindOf( this ) )
		{