Bug 196767 "Finish" button does not take effect when first use CSS file then import CSS style in a library [0303]
Description: "OK" button is disabled when first use CSS file then import CSS style in a library. Build number: 2.2.1.v20070717-0630 Steps to reproduce: 1. New a library, in Outline view, right click to select default Theme->Use CSS File..., select one css file, click "OK". 2. in Outline view, right click to select default Theme->Import CSS Style..., select one css file, click "Select All" button, click "OK". Expected result: "OK" button is enabled. Actual result: "Ok" button is disabled. Error log: N/A
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ThemeHandle.java
* @return the corresponding style
	 */
	public StyleHandle findStyle( String name )
	{
		Theme theme = (Theme) getElement( );
		StyleElement style = theme.findStyle( name );
		if ( style != null )
			return (StyleHandle) style.getHandle( module );
		return null;
	}
	/**
	 * Makes the unique style name in the given theme. The return name is based
	 * on <code>name</code>.
	 * 
	 * @param name
	 *            the style name
	 * @return the new unique style name
	 */
	String makeUniqueStyleName( String name )
	{
		assert this != null;
		SlotHandle styles = getStyles( );
		Set set = new HashSet( );
		for ( int i = 0; i < styles.getCount( ); i++ )
		{
			StyleHandle style = (StyleHandle) styles.get( i );
			set.add( style.getName( ) );
		}
		
		PropertyHandle propHandle = getPropertyHandle( IThemeModel.CSSES_PROP );