Bug 121687 Exception throws when export data in table which inside a grid cell.
Description: Exception throws when export data in table which inside a grid cell. Steps to reproduce: 1. insert a grid. 2. insert one table to one grid cell. 3. insert another table to the other grid cell. 4. export data in two tables. Expected result: Data are exported. Actual result: Exception in: ReportEngineService.getMetaData( )
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/parser/EngineIRVisitor.java
{
		HighlightRuleDesign rule = new HighlightRuleDesign( );
		MemberHandle hOperator = ruleHandle
				.getMember( HighlightRule.OPERATOR_MEMBER );
		MemberHandle hValue1 = ruleHandle
				.getMember( HighlightRule.VALUE1_MEMBER );
		MemberHandle hValue2 = ruleHandle
				.getMember( HighlightRule.VALUE2_MEMBER );
		MemberHandle hTestExpr = ruleHandle
				.getMember( HighlightRule.TEST_EXPR_MEMBER );
		String oper = hOperator.getStringValue( );
		String value1 = hValue1.getStringValue( );
		String value2 = hValue2.getStringValue( );
		String testExpr = hTestExpr.getStringValue( );
		rule.setExpression( oper, value1, value2 );
		if ( testExpr != null && testExpr.length( ) > 0 )
		{
			rule.setTestExpression( testExpr );
		}
		else if ( ( defaultStr != null ) && defaultStr.length( ) > 0 )
		{
			rule.setTestExpression( defaultStr );
		}
		else
		{
			
			return null;
		}