Bug 144106 [Regression]Parameter request page pops up twice while running the report with cascading parameter
Steps to reproduce: 1.Add a cascading parameter group with a parameter 2.Preview Expected result: The parameter request page just pops up once for input value Actual result: The parameter request page pops up twice when inputting parameter value
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
{
		IReportRunnable runnable = (IReportRunnable) this.reportDesignHandle
				.getDesignObject( );
		assert runnable != null;
		ModuleHandle model = runnable.getDesignHandle( ).getModuleHandle( );
		assert model != null;
		return model.getFlattenParameters( );
	}
	/**
	 * @return the parameter handle
	 */
	public ParameterHandle findParameter( String paramName )
			throws ReportServiceException
	{
		if ( paramName == null )
			return null;
		IReportRunnable runnable = (IReportRunnable) this.reportDesignHandle
				.getDesignObject( );
		assert runnable != null;
		ModuleHandle model = runnable.getDesignHandle( ).getModuleHandle( );
		assert model != null;
		return model.findParameter( paramName );
	}
	/**
	 * @return the maxRows
	 */
	public int getMaxRows( )
	{
		return maxRows;
	}