Bug 159380 [regression]Not find DataEngineContextExt class cause all engine/dte smoke testing fail
Description Not find DataEngineContextExt class cause all engine/dte smoke testing fail Steps to reproduce: Run Engine/DTE smoke testing framework Expected result&#65306; Outputs are correct. Actaul result: All outputs are 0kb with Exception: Error happened while running the report. java.lang.NoClassDefFoundError: org/eclipse/birt/data/engine/impl/DataEngineContextExt at org.eclipse.birt.data.engine.api.DataEngineContext.setTmpdir(DataEngineContext.java:374) at org.eclipse.birt.report.engine.data.dte.DteDataEngine.<init>(DteDataEngine.java:71) at org.eclipse.birt.report.engine.data.DataEngineFactory.createDataEngine(DataEngineFactory.java:94) at org.eclipse.birt.report.engine.executor.ExecutionContext.getDataEngine(ExecutionContext.java:694) at org.eclipse.birt.report.engine.executor.ReportExecutor.execute(ReportExecutor.java:99) at org.eclipse.birt.report.engine.internal.executor.l18n.LocalizedReportExecutor.execute(LocalizedReportExecutor.java:38) at org.eclipse.birt.report.engine.layout.html.HTMLReportLayoutEngine.layout(HTMLReportLayoutEngine.java:68) at org.eclipse.birt.report.engine.api.impl.RunAndRenderTask.run(RunAndRenderTask.java:207) at org.eclipse.birt.report.engine.api.ReportRunner.runAndRenderReport(ReportRunner.java:237) at org.eclipse.birt.report.engine.api.ReportRunner.execute(ReportRunner.java:162) at org.eclipse.birt.report.engine.api.ReportRunner.main(ReportRunner.java:118)
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/DataEngineImpl.java
* DtE to prepare.
	 * <p>
	 * During prepare, the DTE does not open a data set. 
	 * In other words, any before-open script on a data set will not be
	 * evaluated at this stage.  That could mean that certain query 
	 * plan generation must be deferred 
	 * to execution time since necessary result set metadata 
	 * might not be available at Prepare time.
	 * @param	querySpec	An IReportQueryDefn object that specifies
	 * 				the data access and data transforms services
	 * 				needed from DtE to produce a set of query results.
	 * @return		The PreparedQuery object that contains a prepared 
	 * 				ReportQuery ready for execution.
	 * @throws 		DataException if error occurs in Data Engine
	 */
	public IPreparedQuery prepare( IQueryDefinition querySpec )
		throws DataException
	{
	    return prepare( querySpec, null );
	}
	/*
	 * If user wants to use data set cache option, this method should be called
	 * to pass cache option information from the upper layer.
	 * 
	 * @see org.eclipse.birt.data.engine.api.DataEngine#prepare(org.eclipse.birt.data.engine.api.IQueryDefinition,
	 *      java.util.Map)
	 */
	public IPreparedQuery prepare( IQueryDefinition querySpec,
	        						Map appContext )
		throws DataException