Bug 162167 Add API IResultIterator.isEmpty to Data Engine.
Current DTE api do not have a method that can be directly used to tell the client whether an IResultIterator is empty or not.We need to add this api for the convenience sake.
engine/org.eclipse.birt.report.engine.tests/test/org/eclipse/birt/report/engine/api/script/RowDataTest.java
{
		private Map expressions;
		public FakeResultIteratorTest( Map expressions )
		{
			this.expressions = expressions;
		}
		public IQueryResults getQueryResults( )
		{
			return null;
		}
		public Scriptable getScope( )
		{
			return null;
		}
		public IResultMetaData getResultMetaData( ) throws BirtException
		{
			return null;
		}
		public boolean next( ) throws BirtException
		{
			return false;
		}
		public Boolean getBoolean( IBaseExpression dataExpr )
				throws BirtException
		{
			return null;
		}