Bug 148747 Design become invalid when I extend a masterpage from Library
The attachment contains a report file and a library file. Reproduce: 1. Deploy the library("lib"), and open the report. 2. Drag Masterpage("page1") from "lib" to report. 3. Reopen the report, it become invalid.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/parser/ReportElementState.java
*            true if this element requires a name, false if the name is
	 *            optional.
	 * 
	 * @see #initSimpleElement(Attributes)
	 */
	protected void initElement( Attributes attrs, boolean nameRequired )
	{
		DesignElement element = getElement( );
		String name = attrs.getValue( DesignElement.NAME_PROP );
		if ( StringUtil.isBlank( name ) )
		{
			if ( nameRequired )
				handler.getErrorHandler( ).semanticError(
						new NameException( element, null,
								NameException.DESIGN_EXCEPTION_NAME_REQUIRED ) );
		}
		else if ( name.indexOf( ReferenceValue.NAMESPACE_DELIMITER ) != -1 )
		{
			handler.getErrorHandler( ).semanticError(
					new NameException( element, name,
							NameException.DESIGN_EXCEPTION_DOT_FORBIDDEN ) );
		}
		else
			element.setName( name );
		if ( element.getDefn( ).canExtend( ) )
		{
			String extendsName = attrs
					.getValue( DesignSchemaConstants.EXTENDS_ATTRIB );
			element.setExtendsName( extendsName );
			resolveExtendsElement( );