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
{
		
		ElementPropertyDefn prop = (ElementPropertyDefn) getDefn( )
				.getProperty( propName );
		if ( prop == null )
			prop = getUserPropertyDefn( propName );
		return prop;
	}
	/**
	 * Validates that the given property name is either a system-defined or
	 * user-defined property.
	 * <p>
	 * Part of: Property system.
	 * 
	 * @param propName
	 *            The name of the property to validate.
	 * @throws PropertyNameException
	 *             If the property is undefined.
	 */
	void validatePropertyName( String propName ) throws PropertyNameException
	{
		if ( getPropertyDefn( propName ) == null )
			throw new PropertyNameException( this, propName );
	}
	/**
	 * Validates the given property value. Validation may map the value onto a
	 * new value that should be used for the actual property update.
	 * <p>
	 * Part of: Property system.
	 *