Bug 122850 Table/list should not be able to be inserted in Master Page mode.
Description: Table/list should not be able to be inserted in Master Page mode. Steps to reproduce: 1. New a report and transfer to Master Page mode. 2. New a datasource and dataset 3. Drag a list/table to page header/footer, bind it to dataset and drag some columns inside. 4. Save and preview Expected result: Insert list/table item in master page should be forbidden. Actual result: They are allowed and preview showed "undefine" in page
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
*         <code>resourceKey</code> is blank or <code>null</code>.
	 */
	public String getMessage( String resourceKey, Locale locale )
	{
		if ( StringUtil.isBlank( resourceKey ) )
			return ""; 
		if ( locale == null )
			locale = ThreadResources.getLocale( );
		
		String msg = translations.getMessage( resourceKey, locale );
		if ( msg != null )
			return msg;
		
		String baseName = getStringProperty( this, INCLUDE_RESOURCE_PROP );
		if ( baseName == null )
			return ""; 
		File msgFolder = getModuleFolder( );
		if ( msgFolder == null )
			return ""; 
		return BundleHelper.getHelper( msgFolder, baseName ).getMessage(
				resourceKey, locale );
	}
	/**
	 * Return the folder in which the design file is located. The search depend
	 * on the {@link #getFileName()}.
	 * 
	 * @return the folder in which the design file is located. Return
	 *         <code>null</code> if the folder can not be found.
	 */
	private File getModuleFolder( )