Bug 188027 PasteAction is diabled
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/elements/Theme.java
name = NamePropertyType.validateName( name );
		if ( name == null )
			name = ModelMessages.getMessage( "New." 
					+ element.getDefn( ).getName( ) ).trim( );
		List styles = slots[STYLES_SLOT].getContents( );
		List ns = new ArrayList( styles.size( ) );
		for ( int i = 0; i < styles.size( ); i++ )
			ns.add( ( (StyleElement) styles.get( i ) ).getName( ) );
		int index = 0;
		String baseName = name;
		while ( cachedStyleNames.contains( name ) || ns.contains( name ) )
		{
			name = baseName + ++index;
		}
		
		element.setName( name.trim( ) );
		cachedStyleNames.add( name );
	}
	/**
	 * Remove some cached name.
	 * 
	 * @param name
	 *            the name of style element.
	 */
	public void dropCachedName( String name )
	{
		cachedStyleNames.remove( name );
	}
}