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
return new ArrayList( derived );
		return new ArrayList( );
	}
	/**
	 * Returns the valid status of this element. Child elements need to
	 * overwrite this method to say in which condition they can be said valid or
	 * not.
	 * <p>
	 * for example, if a JDBCDataSource can not reach the server, then it's
	 * invalid.
	 * <p>
	 * UI needs this method to show different icon for each element in the user
	 * interface.
	 * 
	 * @return true if this element is valid, false otherwise.
	 */
	public boolean isValid( )
	{
		return isValid;
	}
	/**
	 * Sets whether the element is valid.
	 * 
	 * @param isValid
	 *            the valid to set
	 */
	public void setValid( boolean isValid )
	{
		this.isValid = isValid;
	}